Institut für Health Care & Public Management

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Automatische Prozessüberwachung in der Nutztierhaltung : Gestaltung eines Verfahrens zur Extraktion von Prozessindikatoren aus Bilddaten mittels Deep Learning
(2024) Riekert, Martin; Kirn, Stefan
Der Gegenstand der Arbeit sind Verfahren zur Erkennung der Prozessindikatoren zum Liegeverhaltens von Schweinen aus Videobildern. Das Liegeverhalten eines Schweines ist definiert als dessen Position im Stallbereich und ob es liegt oder nicht liegt. Hierzu zeichnen in Stallbereichen installierte Kameras kontinuierlich Videobilder auf, die hinsichtlich des Liegeverhaltens der abgebildeten Schweine analysiert werden. Die Stallposition im Tagesverlauf und die Liegehäufigkeit sind wichtige Prozessindikatoren in der Schweinehaltung. Die Problemstellung liegt in der Korrektheit der Erkennung der Prozessindikatoren zum Liegeverhalten. Bisherige Verfahren treffen zwei Annahmen: Erstens werden nur zur Tageszeit aufgenommene Videobilder verarbeitet, sodass das Liegeverhalten im Dauerbetrieb und insbesondere der Nacht und Dämmerung unerkannt bleibt. Zweitens setzen die Verfahren Homogenität der Stallbereiche voraus, sodass alle Stallbereiche ähnliche physische Eigenschaften besitzen. Diese Annahme beschränkt die Eignung der Verfahren für unbekannte Stallbereiche. Die Problemstellung wird aus der Perspektive des Deep Learning untersucht. Die vorliegende Arbeit trägt zur automatischen kontinuierlichen Erfassung der Position und der Körperhaltung von Schweinen unter Verwendung von handelsüblichen 2D-Kameras in realen Umgebungen unter verschiedenen Lichtbedingungen und Kameraausrichtungen rund um die Uhr bei. In der vorliegenden Arbeit wird untersucht, wie Deep-Learning-Verfahren angewendet und gestaltet werden können, um unter realen Bedingungen kontinuierlich eine hohen mean Average Precision zu erzielen und welche Einschränkungen bei der Anwendung von Deep-Learning-Verfahren bestehen. Das gestaltete und evaluierte Verfahren ermöglicht die Erkennung von Schweinen in einer großen Anzahl verschiedener Ställe, dies beinhaltet das Liegeverhaltens unter Verwendung realistischer Kamera- und Beleuchtungseinstellungen (inkl. Nachtaufnahmen mittels Nahinfrarot).
Arbeitszeitmodelle im Schweizer Gesundheitswesen : qualitative Untersuchung in der Maximalversorgung
(2023) Linggi, Michael; Ernst, Christian
Research into the working time models of physicians is of great importance to ensure the health and safety of patients, to improve the well-being and satisfaction of medical staff, to increase the efficiency of work processes and to counteract the shortage of labor. The dissertation discusses the different working time models in the Swiss health care system, especially in the field of maximum care. It shows the working time models applied in practice as well as the challenges arising from their implemen-tation. It concentrates on the field of surgery (cutting discipline), but is not limited to specific surgical specialties, but follows a generalist approach. The aim of the re-search is to show which working time models function in the complex daily work of physicians in the Swiss model of maximum care and to what extent they can be transferred to other levels of care and countries. Due to the complexity of the topic, the research question was answered with the help of qualitative interviews. Both phy-sicians and administrative staff were interviewed. By means of qualitative content analysis, the various categories were then formed in order to be able to classify the transcribed text passages. The dissertation is based on the results of current research, for which primarily the contributions of generalist research were used. It has been shown that the organiza-tion of working time has a considerable influence on the satisfaction and health of employees. In particular, 24-hour operations and the associated shift patterns play an important role. Theoretical approaches to human, social and psychological capital al-so illustrate why employees are one of a companys most important resources. This forms the basis for the presentation of different working time models and the identifi-cation of influencing factors. Future-oriented aspects are also taken into account, such as the possibility of using robots in surgery to perform various procedures, which opens up additional options for designing new working time models. The findings of the dissertation can be summarized as follows: It is important to con-sider working time models in a global context, as the topic is very complex and multi-factorial. Basically, three levels can be identified that have to be considered when de-veloping innovative working time models: Society, institution and individual. In order to make new working time models possible, structural, societal prerequisites such as the Working Time Act and family-friendly framework conditions are needed. In addition, the institution, i.e. the hospital, must have the courage to break new ground and give employees the opportunity to work in new working time models. Finally, it is also up to the physicians to take personal responsibility and not take advantage of the employer. In addition to this overall approach with the three levels, the following focal points could be derived: Everyday work, work-life balance, research, education and training, career, work content, digitalization and other focal points. These focal points show which topics must be taken into account when developing new working time models. Finally, four working time models were identified as the most common: Part-time, Protected Time, Job Sharing and Home Office. In addition, labor legislation must cre-ate the framework conditions to enable these models to be used in a meaningful way. The findings are transferable to clinics and hospitals in other countries with a competi-tive health insurance system, such as Germany or Austria. This means that the find-ings and recommendations for improving working time models should also be appli-cable in similar legal and organizational contexts. This dissertation on the study of working time models among physicians at the high-est level of care provides an important basis for the further development of such models. The holistic view of the topic and the identification of challenges and focal points contribute to the improvement of future working time models. Hospital and clin-ic management should take these results into account when planning and implement-ing working time models. For future research, similar studies could be conducted in other countries.
Essays in health economics
(2023) Meng, Fan; Sousa-Poza, Alfonso
As the global economy and healthcare evolve, subjective well-being is increasingly becoming a topic of interest in the field of health economics. In this dissertation, we try to investigate subjective well-being from two related aspects: obesity and marriage. Obesity is a global health crisis that has reached alarming proportions in recent years. Defined as an excessive accumulation of body fat, obesity has far-reaching implications for both individ- ual health and society as a whole. Its prevalence has steadily risen, with over 650 million adults worldwide classified as obese, according to data from the World Health Organization (WHO). This epidemic has led to a surge in obesity-related health problems, including diabetes, cardio- vascular disease, and certain types of cancer, making it a pressing concern for healthcare systems and policymakers. Estimates of the cost of obesity are an important basis for the development and evaluation of obesity-related policies. Previous studies have estimated the direct and indirect costs of obesity, but in addition to these, the intangible costs of obesity are also noteworthy. The intangi- ble costs of obesity are associated with a loss of well-being. In addition, obesity-related inequality may also combine with peer effects to lead to lower well-being in obese individuals. So, ignoring the intangible costs of obesity may lead to underestimating the benefits of obesity control policies. Marriage, without a doubt, is a major event in life. People from almost any socio-cultural back- ground consider marriage-related decisions such as whether to get married, when to get married, and with whom to get married. But nowadays, in increasingly countries around the world, mar- riage rates continue to decline and the age of first marriage continues to be delayed, so we sought to analyze whether these trends are related to marriage-related well-being. The contributions of each chapter are shown below: Chapter 2 uses SOEP 2002-2018 data and a life satisfaction-based compensation approach to quantify the intangible costs of overweight and obesity. Previous literature documents the direct and indirect economic costs of obesity, yet none has attempted to quantify the intangible costs of obesity. This study focuses on quantifying the intangible costs of one unit body mass index (BMI) increase and being overweight and obese in Germany. Our results underscore how existing research into obesity’s economic toll may underestimate its true costs, and they strongly imply that if obesity interventions took the intangible costs of obesity into account, the economic benefits would be considerably larger. Chapter 3 uses data from the German Socio-Economic Panel (GSOEP), investigates the changes in the BMI distribution and obesity inequality among German adults aged 18+ between 2002-2018 and estimates the relationship between obesity inequality and subjective well-being. The results show that the rise in obesity prevalence is mainly due to an overall rightward shift of the BMI distribution, accompanied by an increase in left skewness. Over the entire 16-year period, obe- sity inequality increased significantly, especially among females, those with low education levels, and low-income groups. The results also document a significant association between different measures of obesity inequality and subjective well-being, especially among women. Chapter 4 explores the trends in the subjective well-being (SWB) of never-married people (referenced with the married) and the factors that account for the gaps in SWB between never- married and married people. By employing a harmonized data from surveys conducted in six distinct countries, namely Australia (HILDA), South Korea (KLIPS), Russia (RLMS), Switzerland (SHP), Germany (SOEP), and the United Kingdom (BHPS and UKHLS), our analysis discerns a consistent and statistically significant association between never-married status and lower levels of life satisfaction, a relationship that has exhibited no substantial alteration over time. Particularly noteworthy is the discernible reduction in life satisfaction among never-married individuals in South Korea in comparison to their married counterparts. The thesis concludes with a short summary in chapter five.
Incentives in health care provision
(2022) Weinert, Johanna Katharina; Schiller, Jörg
The importance of finding ways to ensure high quality health care provision in a cost-effective and efficient way becomes a more and more pressing issue considering the challenges many economies currently face due to ageing populations, rising costs caused by advancements in medical technology or an increasing shortage in qualified personnel. Chapter 2 analyzes empirically how the introduction of a surgical suite governance document affects punctuality in first case of the day starts. Delays in first cases are an indicator for inefficiencies in operating room utilization. Because operating rooms constitute a major driver in hospitals’ operating costs, clinic management has a strong interest in incentivizing process efficiency. This analysis focuses on the implementation of a surgical suite governance document, which explicitly specifies the starting time of the first case of the day and formulates scheduling rules. First case punctuality is an easily observable and measurable performance indicator, which is associated with only minor tracking efforts and consequently low costs. The analysis uses a quasi-experimental setting, which arose from the lagged implementation of an identical governance document in two different hospital sites belonging to the same hospital group. To assess the effect of the governance document empirically , a difference-in-difference estimation approach is implemented. Results indicate that the introduction of a surgical suite governance document is associated with significant reductions in first case delays. In conclusion, a surgical suite governance document seems to offer a promising tool to incentivize health care workers to use costly resources like surgery capacities more efficiently. Chapter 3 analyzes the effects of a reimbursement change - from fee-for-service paid out-of-pocket (OOP-FFS) to a capitation fee per patient - on health service provision. This change was part of a selective contract in outpatient pediatric care introduced by a large German sickness fund in 2014. The present analysis aims at deriving further insights on how reimbursement affects service provision and at offering guidelines for future designs of selective contracts. To reflect the special features of the analyzed selective contract, namely that incentives change for both the pediatricians and the patients simultaneously, a theoretical model is set up to derive a testable hypothesis. The model predicts that given pediatricians are not only monetarily incentivized (but also sufficiently concerned about patients’ well-being) and that costs associated with screening provision are relatively small, reimbursement change from OOP-FFS to capitation will induce an increase in service provision. Using a generalized difference-in-difference approach, the theoretically derived hypothesis is tested empirically. Results indicate that the change from fee-for-service paid out-of-pocket to a capitation fee per patient did lead to a significant increase in provided screenings as the number of diagnoses more than doubles for pediatricians enrolled in the program. These findings indicate that physicians are not solely driven by monetary incentives and that capitation per patient offers a valuable tool to ensure cost control yet simultaneously ensure effective health care provision. Chapter 4 examines to which extent policymakers are able to incentivize hospitals to increase quality provision by actively fostering the link between performance indicator reporting and hospitals’ reputation. A better understanding of policymakers influence on quality incentives is crucial as empirical findings show that hospitals vary with respect to quality provision, implying that potential for improvements exists at least for some service providers. By fostering the link between hospitals’ outcome-based performance indicators such as mortality-, readmission- or complication rates and reputation, policymakers are able to affect hospitals’ market share and thereby ultimately hospitals’ incentives for quality provision. Ways to strengthen the aforementioned link are manifold, e.g. by raising awareness about the existence and importance of hospital performance reports or by improving populations’ health literacy to ensure that patients are able to decode the information provided by performance indicators correctly. The main finding is that a strengthened link between performance indicators’ realization and hospitals’ reputation does not necessarily result in stronger incentives for quality provision. In the case where the degree of competition is sufficiently low and the costs associated with quality provision are sufficiently high, an intensified link between performance indicators and reputation induces a decrease in quality provision. If the opposite is true, strengthening the link between performance indicators’ realization and hospitals’ reputation always induces an increase in quality provision.
The impacts of conflict and climate change on food security and nutrition in Chad
(2023) Bachofer, Robert Paul; Sousa-Poza, Alfonso
This dissertation aims at providing an overview of how armed conflict and climate impact food security and nutrition in the African country of Chad. It analyzes the impacts of the Boko Haram insurgency on food security and nutrition, and those of annually recurrent droughts on households’ coping strategies. Placing the Republic of Chad in the context of the administrative regions of surrounding countries, where Boko Haram and its splinter groups operated at the time of their greatest territorial expansion (Extreme Nord in Cameroon, Lac in Chad, and Diffa in Niger, as well as the Nigerian states of Borno, Yobe, and Adamawa), it covers the timeframe from late 2009 to 2016. On the qualitative side, a systematic literature review on the impacts of Boko Haram on food security and related concepts in the study area, a review of conflict databases and press coverage of Boko Haram’s activities, and semi-structured interviews of Chadian security experts help to locate where and when the insurgency was active, the violence it perpetrated, and the impacts it had. On the quantitative side, the thesis leverages DHS data of 1997 and 2010, MICS data of 2000 and 2015 for childhood malnutrition indicators. The 2011, 2013, 2014, 2015 and 2016 ENSA waves are used for household food security indicators. Across the broader Lake Chad region, Boko Haram activity led to the displacement of food producers, interruption of migration routes of pastoralists, increased exposure to cattle rustling, and transport restrictions affecting food markets. It is also associated with changes in trade routes and border closures leading to price fluctuations, market closure and decrease in market activity, reduction in smallholder farmers’ income, and curbing physical access of consumers to food markets due to the destruction of infrastructure and security concerns. These factors contributed to increases in wasting, stunting, and child mortality rates, decreases in school enrolment and years of schooling, and limitations in access to health care. On the macroeconomic level, agricultural output, GDP, and other development indicators have been affected negatively. However, on the micro level, many studies focus on the insurgency’s impacts on displacement, in the form of refugees and IDPs within specific camps. These populations struggle with their loss of agro-pastoralist livelihoods, and with limited access to land and water to sustain them. Coupled with low employment rates, this results in low income across camps. However, whether this results in lack of food availability and diversity differs significantly from camp to camp, and access to health, education, and other basic service is highly unequally distributed as well. Concerningly, trading food for sex is a practice in at least some camps. Centering in on Chad itself, the thesis exploits the fact that Boko Haram perpetrated only criminal but not political violence between 2010 and 2014. During this period, insurgents plundered and pillaged Chadian villages in the seasonal wetlands of Lake Chad, and committed other criminal acts, but did not engage Chadian security forces for political gains; hence, this setup allows to isolate the impacts that terrorist organizations can achieve through purely criminal violence. Applying a DID approach, the dissertation finds that such criminal violence causes deteriorations in the z-scores of underweight and wasting of children under the age of five years by -0.085 points and -0.305 points, respectively. It finds that the insurgency’s criminal violence causes a decrease of 31.7 percentage points in the participation of households in agricultural activities and a decrease of their dietary diversity by 53.7 points. These impacts are large, especially considering that criminal violence perpetrated by Boko Haram in Chad received little to no international attention. The impacts of seasonal drought on food security, however, are much more measured. Out of five coping strategies assessed, seasonal drought has impacts to a statistically significant degree on only two: The prevalence of households selling non-productive assets and the prevalence of using their savings increases by 7.1 percentage points and 7.6 percentage points, respectively, when drought exposure increases by 1 percentage point on a low administrative level. Estimates of heterogeneous treatment effects and other robustness tests support a causal interpretation of these coefficients, which are obtained through two-way fixed effect estimations. These findings do not mean that drought-affected households do not enact other coping strategies, too. It merely means that seasonal drought likely causes them to use only two very specific coping strategies, but it does not cause the use of others.
Baseline assessment and cost analysis of a supplementary feeding intervention on Adivasi children in West Bengal, India : How to diversify diets with locally available resources cost-effectively to reduce the burden of child and maternal undernutrition and anaemia?
(2022) Golembiewski, Silvia; Sousa-Poza, Alfonso
This dissertation presented and analyzed the living, health and nutrition situation of tribal Adivasi children (aged 6-39 months) as well as of their mothers living in rural Birbhum district, West Bengal, India. It was found that extended families use to have higher incomes (p<0.05) compared to nuclear families and that higher education of mothers (having completed at least class eight) is associated with higher incomes, too (p<0.05). Higher incomes were further found associated with a lesser incidence of moderate and severe anaemia amongst children (p<0.05). Further, active child caring was found to decrease the incidence of stunting (p<0.05, for caring efforts of three hours or more per day) - while mothers tied up in cooking (with cooking efforts of 6 and more hours a day) showed to have bigger likelihood of having a wasted or underweight child (p<0.05). It was suggested that the provision of gas cookers along with cooking gas to Adivasi families may be helpful to free mothers to care more actively for their children and reduce therewith child undernutrition. The dissertation further revealed that either father or mother deciding alone how to expense available income is superior to joint spending decisions - and it was in fact HHs with mothers deciding alone which showed the largest share of children with no or merely mild anaemia (p<0.05). It was suggested, accordingly, that mothers may be entrusted to manage a food budget on their own. Very importantly, the nutritional status of children and their mothers was found to be linked, where mothers with adequate BMI (18.5 and higher) had less often than expected a wasted child (p<0.001) and also less often an underweight child (p=0.001). Severe thin mothers (with a BMI<16.0) showed biggest likelihood of having a child with at least one anthropometric failure. No significant association was found between the anaemia status of the mother and her youngest child (p>0.05). Still, non-anaemic mothers showed bigger likelihood of having non-anaemic children than mothers with poorer Hb statuses, and - the other way around - mothers with severe anaemia showed the biggest likelihood of having children with moderate anaemia. It was argued, accordingly, that not only children but also their mothers should be better nourished in order to break the vicious circle of undernutrition - with a focus on lactating mothers who have highest nutritional intake needs. Overall, 94 percent of tribal Adivasi children were found anaemic (n=307, age range: 6-39 months, Hb<11g/dl) as well as 86 percent of their mothers (n=283, Hb<12g/dl). Anaemia in children was found significantly associated with the age of the child (p<0.001) where Hb was found to rise with increasing age and children above three years reached mild forms of anaemia - while children aged 6-23 months commonly suffered from moderate anaemia. Further, the consumption of fruit was found to decrease the incidence of moderate and severe anaemia (p<0.05). There was also a link between child undernutrition and the occurrence of severe anaemia, where children with no anthropometric failure (CIAF indicator) showed lesser likelihood to develop severe anaemia compared to children with at least one anthropometric failure (p<0.05). Seeing the high incidence of anaemia and interlinking to child undernutrition as well as interlinking of nutritional status of children and their mothers - the question arose how to overcome child as well as maternal undernutrition and anaemia? The present comparative intervention study conducted in 21 tribal villages found that providing diversified meals three times a week to children aged 6-39 months rose their mean Hb by 0.98g/dl (compared to 0.45g/dl in the CG); it was found that after 12 months children receiving the diversified meals showed a bigger share of non-anaemic or only mildly anaemic children compared to the CG (p<0.05). Further, children who had received the diversified meals showed bigger likelihood of achieving Hb increases which belong to the top 30 percent of all reported Hb increases (amounting to 1.40g/dl and more) after 12 months of intervention compared to the CG (p<0.01). It was argued, accordingly, that providing nutritious meals to undernourished tribal Adivasi children increases Hb and reduces anaemia. No significant difference in the distribution of non-anaemic and mildly anaemic children versus moderately and severely anaemic children could be found when comparing a group of children who had received a leaf powder of Moringa and Amaranthus along with diversified meals to the CG (p>0.05) and when comparing a group of children who had received a (low dosed) micronutrient sprinkle along with diversified meals (p>0.05). A cost-effectiveness analysis of 425 locally available foods has been conducted in order to work out those foods delivering highest nutrient density in relation to their retail cost (adjusted for edible portion). Foods from the FGs cereals and millets, vegetables, and roots and tubers belonged more often to the top 30 percent of cost-effective foods as per winter-price analysis (p<0.001) - while also grain legumes became cost-effective as per summer-price analysis (p<0.05). While the overall cost-effectiveness of FGs showed little difference considering winter- and summer price analyses, the cost-effectiveness of specific foods within some of the analyzed FGs did actually change (especially in case of vegetables). It was recommended, accordingly, to use most cost-effective locally available foods to nourish undernourished children and mothers adequately - and to consider also seasonal price changes of foods thereby. The developed aggregate cost-effectiveness indicator covered 38 nutrients. Further, five anti-nutritive elements to be limited in the diet of undernourished individuals had been considered: oxalate, phytate, polyphenols, sodium as well as dietary fibre. The need to process foods rich in anti-nutrients in order to cover the RDAs of undernourished children and mothers was highlighted - working out a categorization of anti-nutritive elements in low (≤ 4th percentile), medium (> 4th until ≤ 8th percentile), high (>8th until ≤ 9.5th percentile) or very high (> 9.5th percentile) contents. On the basis of knowing most cost-effective locally available foods and assessing also their anti-nutritive elements, a weekly meal schedule has been worked out in cooperation with the nutritionist Caroline Stiller (who was the second PhD candidate in this twin PhD project and knows the local setting well). It became clear that the RDAs of moderately malnourished children and their mothers can hardly be fully covered with locally available foods alone - where a deficit of 20 and more percent of the RDA remained with regard to vitamins A, E, B1 and B2, as well as of zinc and linoleic acid (children), with regard to vitamins A, E, B1, B2 and B9, as well as of potassium and linoleic acid (lactating women), with regard to vitamins B1, B2 and B9, as well as of iron, potassium and linolenic acid (pregnant women), and with regard to vitamins B1 and B2, as well as of iron, potassium and linolenic acid (non-pregnant and non-lactating women). It was further found that the costs associated with the suggested cost-effective and nutrient-dense weekly meal schedule exceeded available family budgets (calculated based on n=66 HHs and with respect to consumed portion sizes of children and mothers) by 217 percent in case of children (with a weekly cost of 267 Rs. rather than the available 144 Rs.), and by 200 percent in case of lactating, pregnant as well as non-pregnant non-lactating mothers. The role of government services (AWCs, the PDS, and the MGNREGA), kitchen gardening/wild plant collection, own fishing activities and crop diversification in covering this deficit was enumerated and it was found that AWCs are able to cover the largest part of the weekly financing deficit (amounting to 34 percent in case of children), followed by kitchen gardens/wild plant collection (24 percent). As breastfeeding is deeply rooted in the Santal Adivasi communities (96 percent of mothers, n=275, were found to breastfeed their youngest child - with a mean age of 21.2 months), it is proposed in this dissertation that lactating women should be included as beneficiaries of AWCs in order to cover their nutrient needs and break - finally - the circle of undernutrition where children and mothers need to be seen together, rather than focusing merely on children in the well-known 1000-days window of opportunity.
Mathematische Optimierung der Sterilgutversorgung in medizinischen Einrichtungen unter Berücksichtigung von Einweg- und Mehrweginstrumenten
(2021) Hummel, Rebecca Madeleine; Ernst, Christian
Due to demographic change, healthcare systems in industrialized countries are confronted with increases in service volumes and costs combined with high quality and care demands. Increased efficiency is an important - if not the most important - means of meeting this challenge. Logistics processes, which account for up to 30% of total costs, offer a starting point for efficiency improvements in hospitals. Cost savings of up to 50% can be achieved by optimizing logistics processes. In particular, optimization in the area of hospital logistics offers the opportunity to reduce costs while maintaining quality assurance. This thesis considers the logistical process of sterile supply, which has the task of providing and preparing sterile surgical instruments. As an sub-process of the surgical process, it is of essential importance both from the point of view of economy and quality. The aim of this work is to develop an optimization approach for the sterile supply process which, with the aid of a mathematical model, combines the decision on the grouping of reusable instruments in trays and the decision between the use of a disposable or a reusable instrument. The combination is intended to unlock optimization potential from synergies of the interdependent decisions. The research contribution of the thesis consists, on the one hand, in a systematic literature review on the state of the art of sieve optimization and the disposable-reusable decision, and, on the other hand, in the development of a new problem, which has not been addressed in the literature before, but is highly relevant in practice. The problem is represented in the form of a mathematical model and a mathematical optimization approach is developed to solve the problem. The optimization model is implemented in the optimization software GAMS and applied to a practical case study using the solver CLPEX. For the purpose of an efficient implementation, an algorithm for the linearization of model variables is also designed. Based on the case study, the savings potential of the optimization approach for the gynecological clinic of a maximum care provider can be estimated at almost 80,000 euros per year.
Smarte Städtebauliche Objekte für eine adaptive Stadt : ein Verfahren der Künstlichen Intelligenz zur Erhöhung der Wohlfahrt
(2021) Hubl, Marvin; Kirn, Stefan
The objective of the thesis is the advancement of urban areas with intelligent information technology to enhance urban life. In doing so, social inclusion of people with motor impairments is of particular interest. At this, an important group is the set of older adults. The aspired advancement aims at enabling self-determined participation in urban life, and hence in social life, up until old age: Participation in social life essentially depends on the opportunities for self-determined exertion of outdoor activities. Motor impairments in old age lead to a perceived significant reduction of safety in urban areas and hence concerned people are worried of using the urban area. To counteract the resulting avoidance of outdoor activities the thesis pursues the approach to transform urban objects by means of technologies of the Internet of Things into novel so-called Smart Urban Objects that actively provide support in outdoor activities. Smart Urban Objects are equipped with sensors, actuators and information processing capabilities and can adapt to individual requirements of pedestrians. Due to age-correlated motor impairments, there are for example special requirements for seating. Besides the information technological transformation of single urban objects, there are furthermore important requirements for networked Smart Urban Objects. By means of intelligently coordinated, goal-oriented availability of the supportive functionalities of single Smart Urban Objects, the urban area as overall system is enabled for adaptivity with respect to pedestrians requirements. The thesis studies the conception for an adaptive city with a safety-engineering approach at the example of smart seating and develops a method for an intelligent coordination of the networked Smart Urban Objects. For an accurate allocation of single smart seats as public objects with respect to individual requirements a welfare criterion is applied which shall avoid unfairness. Using methods of Artificial Intelligence the thesis develops a heuristic procedure for finding a solution according to the welfare criterion. This implements aspects of the theory of justice by John Rawls that underlie the welfare criterion for the example of the urban area. A scenario-based simulation substantiates that the developed solution approach can effectively enhance the safety-oriented welfare in the urban area.
It is not about spinach : a food justice perspective on urban agriculture in Cape Town and Maputo
(2021) Paganini, Nicole Maria; Sousa-Poza, Alfonso
The world’s rapid urbanisation has presented multiple challenges to societies and the environment and strained the sustainability and equity of urban food systems. In discussions on the future of the world’s cities and their food security, urban agriculture has gained attention for its potential to contribute to food supply and dietary diversity, generate income for urban producers, and provide various multifunctional benefits such as environmental services, education, and community building. The dissertation followed a conceptual approach that applies a food systems perspective on urban agriculture and uses urban agriculture as a means to identify food justice patterns. In addition, this thesis contributes to participatory action research methodology by shifting focus to the concept of democratisation processes in research. Co-research is a more radical and inclusive form of participatory action research that involves actors and groups from marginalised communities in all research steps. Communities are involved in the study design, problem posing, decision-making around methodology, data collection, analysis and triangulation, and scaling of activities. This process fosters ownership of the gathered results through mutual and transformative learning, and hence, could become more valuable than the results themselves. The food system in Cape Town is highly segregated, as is the city itself: the legacy of apartheid-era planning left an affluent and prosperous city centre surrounded by lower-income areas populated largely by People of Colour who face daily challenges in accessing food. Urban agriculture is practised in the townships of Cape Town by hundreds of farmers—most of them People of Colour, unemployed, elderly, female home growers—and thousands of backyard growers who cultivate a variety of vegetables mostly on small plots. The food gardens are either on public or private land: land is leased for short periods from public institutions such as schools or clinics or leased from municipalities, which is a lengthy and—for many farmers—opaque process. NGOs, with support from the Municipality, introduced urban agriculture as a poverty alleviation strategy to combat high rates of food security in the marginalised parts of the city. Decades of support have hampered the establishment of community-driven food solutions and led to dependencies on NGOs for inputs, marketing, and acquisition of new knowledge. These farming activities play an insignificant role when it comes to household contribution. Food is produced in highly confined and troubled spaces in informal settlements, almost exclusively for a niche market of middle/upper class consumers in the wealthier city centre. Maputo’s food system is strongly influenced by food imports from neighbouring South Africa, by its rapid growth, and by migration from the rural areas of the country where selfsustaining family farming is a primary livelihood strategy. In the urban and peri-urban area of Mozambique’s capital, the zonas verdes (green zones) were established to combat the city’s severe food insecurity crisis after the colonial era. These horticultural production sites have remained vibrant production areas. Urban agriculture is largely commercialised and plays a key role supplying the city with specific horticultural products, mainly cabbage and lettuce. Informal traders buy crops directly from the fields and sell them in Maputo’s local markets and street stands. Four of five farming families indicate that the income they generate in this activity is their main source of revenue. Another estimated 40,000 people earn their livings by supporting urban agriculture through activities such as trading, selling, pesticide application, and transportation. Like Cape Town, it is mainly women who are involved in urban agriculture in Maputo’s fields. Understanding urban agriculture through a food systems lens was crucial in examining the potentials and challenges of urban agriculture. Applying a co-research approach in Cape Town allowed investigations that fostered participating farmers’ agency over the findings and led to the creation of a strong network that carried the research beyond the scope of this project. The mutual contextualisation of the results gathered in an inclusive research process into food justice theory revealed farmers’ in-depth understanding of structural inequalities within food systems in cities. Food justice theory is mainly applied in case studies in the North and looks at historical context and trauma, systemic challenges, and marginalisation in ethnicity, class, place, time, and gender. These research findings from two case studies in the South add to our understanding of marginalisation in urban agriculture in Cape Town and Maputo and shed light on the importance of intersectionality as a contextual component of food justice.
Older adults’ internet use, outdoor activity, and the urban environment : empirical analysis
(2021) Schehl, Barbara; Kirn, Stefan
In an ageing society, information technology (IT) can be a powerful tool to support older adults in staying physically, mentally, and socially active. A growing number of studies show positive effects of Internet use on active ageing. Specifically, understanding the relationship between older adults’ Internet use and their participation in outdoor activity has gained attention. However, little is known about the role of specific online activities, as previous research mainly considered general Internet use, e.g., writing emails and browsing the Web, which does not provide a rationale for increased outdoor activity. Another important factor affecting outdoor activity is the urban environment in which older adults live, especially as the environment can either motivate or hinder participation in outdoor activity. Against this backdrop, the aim of this thesis is to get a better understanding of the association between Internet use, the urban environment, and participation in outdoor activity. By adopting an ecological perspective, this dissertation is first in comprehensively assessing this association. Three studies provide empirical insights into patterns of factors and contribute an enhanced understanding of the association between older adults’ Internet use, the urban environment, and outdoor activity. In summary, this thesis contributes to a relevant growth of knowledge on older adults’ Internet use and outdoor activity. The approach in this thesis uncovered important differences in the roles of individual factors as well as environmental factors in explaining older adults’ outdoor activity. Based on this contributions, important implications for research can be identified. For instance, future research can use the conceptual framework as a basis to investigate further types of outdoor activities and further types of online activities, such as social networks and messaging services which attain increasing relevance for the group of older adults. Further, this dissertation also has some practical implications, for example, as all three studies showed that socio-demographic predictors play important different roles, the findings are specifically relevant to identify specific groups of older adults. For instance, developers and providers can tailor their services to the needs of older adults, e.g., by designing responsive and barrier-free interfaces that adapt to individual capabilities in cognition, vision, and motor function. Concluding, older adults should be encouraged to go online because the Internet increasingly provides information about opportunities and offerings in the city. The findings of this dissertation provide a rationale for the development of online services that offer neighborhood information and ultimately support older adults to be active outdoors.
Essays on remuneration systems of financial advisors
(2019) Weinert, Markus; Schiller, Jörg
Various policy interventions aim at preventing consumers from inadequate financial advice. One important issue that is often subject to intense discussions is the regulation of financial advisors compensation. In most countries, financial advisors are remunerated by product providers via commissions. Concerns are, that this practice leads to biased advice, since an advisor then has an incentive to recommend the product with the highest commission instead of the most suitable product. In order to circumvent the aforementioned incentive problems, consumer protection agencies and regulators propose that financial advisors should exclusively be compensated by consumers via a fee-for-advice. Even though, enacting a ban on commissions constitutes a severe intervention for financial advice markets, the effects of such a regulatory measure are only inadequate studied. The aim of this dissertation is to derive a deeper understanding of how a ban on commissions affects these markets. The three essays in the present thesis analyze the effects of a ban on commissions on bias in advice, total welfare and competition between product providers. The first essay considers the effect of a ban on commissions on the bias of advice in a theoretical model. If consumers ask for reasons and explanations in the advice process, why a particular product should suit their needs, an advisor faces transaction costs for recommending a product. These “persuasion costs” are intuitively low for a product, which is initially preferred by consumers (standard product), and high for a product, which is in consumers eyes unlikely to satisfy their needs (specialized product). The theoretical model shows that advice might not be solely distorted by commissions, but also by these persuasion costs. Therefore, advice can also be biased when consumers exclusively compensate the advisor. The extent of biased advice depends crucially on market shares of product providers and on potential reputational costs for the advisor enforced by market discipline. The second essay theoretically analyzes welfare effects of fee-based and commission-based remuneration systems for financial advisors. In markets, where advice is essential for consumers, product providers usually cannot sell their products directly to consumers. In these markets, commissions do not only serve as a compensation for the advisor, but also as a channel for competition between product providers. Consequently, a regulatory ban on commissions should be considered as a two-sided coin. On the one hand, a ban on commissions may reduce distortion in advice, but on the other hand, it may restrict competition between product providers. The analysis shows, that product providers have different incentives to compete through commissions depending on their market shares, consumers product valuation and potential reputational costs for the advisor. If the difference of commissions for different products is sufficiently small in equilibrium, a commission-based remuneration system leads to a strictly higher total welfare in comparison to a fee-based remuneration system due to a higher fraction of consumers, who are matched with their best suitable product. Otherwise, total welfare is higher under a fee-based remuneration system. The third essay theoretically analyzes whether and how product providers are able to compete in markets where products cannot be sold directly to consumers and commissions are banned by regulation. In particular, two possible channels are considered: Competition through product prices and competition through informative advertising. If a product provider engages in informative advertising, consumers may already be familiar with certain product characteristics before consulting an advisor. By this, advisors persuasion costs for the advertised product may be lower in an advice process, which results in a higher incentive to recommend the advertised product in comparison to other products. In addition, product providers are able to steer advice towards an advertised product. It is shown, that competition through product prices does not take place in equilibrium. However, informative advertising may serve as a channel for competition between product providers if the effect of steering advice is sufficiently high. Analogous to commissions, product providers incentives to engage in informative advertising depend on market shares, consumers product valuations and potential reputational costs for the advisor. In summary, this thesis provides detailed insides of an advice process and the affiliated interaction of driving factors, which influence the quality of advice. The underlying analysis shows that a fee-based remuneration system for financial advisors does not constitute a universal remedy for biased advice and total welfare losses in the corresponding markets.
Obesity inequality and the changing shape of the bodyweight distribution in China
(2018) Nie, Peng; Ding, Lanlin; Sousa-Poza, Alfonso
Using data from the China Health and Nutrition Survey (CHNS), this study analyses changes in bodyweight (BMI and waist circumference) distributions between 1991 and 2011 among adults aged 20+ in China. To do so, we quantify the source and extent of temporal changes in bodyweight and then decompose the increase in obesity prevalence into two components: a rightward shift of the bodyweight distribution (mean growth) and a (re)distributional skewing. Our analysis reveals a clear rightward distributional shift combined with a leftward skewing. Although the relatively large size of this skewing in the first decade analysed reflects an increase in obesity inequality, this inequality growth subsides in the second decade. Nevertheless, over the entire 20-year period, obesity inequality increases significantly, especially among females, younger age groups, rural residents and individuals with low socioeconomic status.
Essays on long-term care and health insurance
(2018) Schreckenberger, Christopher Karl Ludwig; Schiller, Jörg
This thesis contributes to the literature on the impact of two individual options that may help to alleviate the financial pressure on the public sector with respect to health and long-term care expenditures. A particular focus is on the German health insurance and long-term care insurance (LTCI) system. The first option refers to the shifting of LTCI and health insurance coverage from a public system to markets for voluntary private health insurance (VPHI) and private LTCI. These private insurance markets may suffer from inefficiencies due to asymmetric information and selection effects, such as adverse selection. Hence, three papers in this thesis analyze selection effects in markets for VPHI and private LTCI. The first paper (chapter 2) reviews the empirical work on asymmetric information and related selection effects in markets for private LTCI and in the U.S. market for Medigap insurance. After providing an overview of the existence of selection effects in these markets, the review examines the evidence on several potential sources of selection. Regarding the latter, a focus is on the role of private information that individuals have on their risk type, on the role of the individual’s risk preferences and of sociodemographic characteristics. Following the review, two empirical papers analyze selection effects in the German markets for complementary private LTCI (chapter 3) and for supplemental dental insurance (chapter 4). Both markets have in common that they provide voluntary private insurance coverage for residual out-of-pocket expenditure risks not covered by statutory LTCI or health insurance in Germany. In addition, the ex-ante premium differentiation is rather limited in these markets. This makes these markets prone to selection effects. Using a large dataset on more than 98,000 individuals from a German private insurance company, the findings in chapter 3 suggest that advantageous selection is the dominating type of selection in the German market for complementary private LTCI. Examining potential drivers for selection, the analysis indicates that the occupation as well as the residential location are observable characteristics that are not used for pricing, but that contribute to advantageous selection through the socioeconomic status. The holding of supplemental health insurance policies is another observable attribute that affects the selection behavior. Analyzing the selection behavior within a dynamic framework, the analysis shows that the uptake and the cancellation of LTCI policies are associated with changes in health insurance payouts. Moreover, individuals with financial problems and with a lower socioeconomic status are more likely to drop complementary LTCI coverage. Based on survey data from the Healthcare Monitor of the Bertelsmann Stiftung, the findings in chapter 4 do not reveal a significant correlation between insurance coverage and risk in the market for supplemental dental insurance in Germany. Since one possible explanation for this finding is heterogeneous selection leading to an offsetting of adverse and advantageous selection, a large set of potential sources of selection effects is tested. The results indicate that the holding of other supplemental health insurance policies is a main driver for advantageous selection in this market. The findings in this chapter provide solid evidence that this insurance market suffers from asymmetric information and selection effects even though the correlation between insurance coverage and risk is not statistically significant. Instead of shifting insurance coverage to a private insurance system, another option to alleviate the financial burden in a public health insurance system, which is analyzed in this thesis, refers to the promotion of preventive health care. Specifically, the fourth paper (chapter 5) empirically examines the effectiveness of a nationwide population-based skin cancer screening (SCS) program that was implemented in Germany in 2008. To this end, panel data from 2000 to 2013 of the Eurostat database on subregions in 22 European countries are exploited. Using fixed effects methods, the results show a positive and robust effect of the German SCS program on the diagnosis rate for malignant skin neoplasms, but no significant impact on the melanoma mortality rate. The former suggests that this program is effective in terms of an increased diagnosis rate for malignant skin neoplasms and may therefore contribute to an improved detection of skin cancer at an early stage.
Aspects of demand-side oriented insurance of volatile food prices in developing and emerging countries
(2018) Hochscherf, Julian; Schiller, Jörg
The dissertation is concerned with the relation between formal and informal risk management in developing and emerging countries in the context of rainfall and food price variability. The dissertation contains three research projects. In order to systematize the literature on welfare effects of food price volatility and rainfall risks and the related coping strategies, a systematic review on the quantification of these two risk types has been performed. Many studies in the recent past have been published to quantify poverty effects of materialized risk such as drought events or the consequence of the 2008-09 food price crises in emerging and least developed countries. As agrarian economies in least developed countries heavily depend on the correct onset and amount of rainfall quantities, rainfall failures are likely to have adverse consequences for household income and its volatility. In addition, agrarian households in least developed countries are mostly net food consumers and thus highly dependent on the realization of food prices. The review systematizes the empirical evidence on adverse income effects of drought events and food price increases as well as it summarizes the risk management and coping strategies directly linked to these two shock types. A particular emphasis will be given to the stabilizing power of labor markets and adaptation through consumption responses. The second paper is concerned with informal risk management strategies taken out by agricultural households, in particular with the instrument of labor time allocation. Subsistence farmers in low income countries are confronted with multiple risks. In reaction to them, farm households have developed strategies to cope with yield risks to self-insure against these income shocks. Recent developments in global food markets have increased food price volatility, which, in particular, puts low-income households at risk. When small-scale farmers allocate their labor time over different income generating activities, they face the risk of uncertain purchasing power of income in the presence of food price variability. Thus, the paper analyzes the labor time allocation decision between self-employment and wage labor, taking into account the uncertain purchasing power of wages resulting from food price volatility and the farm production risk induced by rainfall variability. Using a panel structured household data set containing consumer-producer households in rural India, the labor time allocation decision between farming and labor market participation will be analyzed and the effect of production and food price uncertainty on labor time allocation will be estimated. The analysis reveals counterintuitive time allocation effects of risk. The third project is concerned with formal insurance demand by farm households and the interrelatedness between formal and informal risk provision. For this purpose, a data set for a weather index insurance demand product has been analyzed. Index based microinsurance as a tool to insure the income of agriculturally active households has triggered extensive discussions in the literature. Despite the convincing theoretical argumentation, the demand for these products stays behind expectations. Several studies revealed effects impacting the demand for index insurance, such as liquidity constraints, basis risk, lack of understanding and trust in insurers and products alike. This paper takes a different perspective and hypothesizes that low demand is due to heterogeneous risk exposure towards weather variability among potential insured resulting from informal risk management. The paper tests the impact of income heterogeneity as a measure of risk exposure on insurance demand and finds that risk exposure negatively affects insurance demand. In order to increase demand, it is concluded that product design should emphasize more the importance of income risk composition and exposure of potentially insured. The dissertation concludes with a critical discussion of how to reconcile formal and informal risk management practices and gives policy implications of how to innovate existing formal insurance products to increase demand.
Beitrittsentscheidungen zu Multiagenten-Organisationen : ein Revenue Management-basierter Ansatz
(2018) Premm, Marc; Kirn, Stefan
Der Forschungsbereich Multiagentensysteme hat sich seit den späten 1970er Jahren als Teilbereich der verteilten künstlichen Intelligenz (VKI) etabliert. Gegenstand dieses Forschungsbereichs sowie dieser Arbeit sind Softwareagenten, die als Softwaresysteme zielorientiert agieren und mittels Lernverfahren eine gewisse Autonomie gegenüber ihrem Entwickler erlangen. Softwareagenten ist es möglich, sich zu Multiagentensystemen zusammenzuschließen. Multiagentensysteme sind folglich offene Systeme, aus denen Softwareagenten ein- und wieder austreten können – im Allgemeinen ohne globale Kontrolle. Hieraus ergibt sich eine gewisse Flüchtigkeit sowohl der Mitgliedermenge als auch der Interaktionsstrukturen eines Multiagentensystems und somit eine eingeschränkte Möglichkeit zur Steuerung des nach außen hin wahrnehmbaren Systemverhaltens, welcher es beim Einsatz von Softwareagenten in kommerziellen Anwendungen im Allgemeinen bedarf. Multiagenten-Organisationen bilden einen Ansatz um die betriebswirtschaftliche Organisationstheorie zur internen Strukturierung von Multiagentensystemen zu nutzen und folglich auch deren Außenverhalten zielgerichtet zu steuern. Diese Arbeit versteht Multiagenten-Organisationen als auf Dauerhaftigkeit ausgelegte Zusammenschlüsse von mehreren unabhängigen Softwareagenten, die durch vertragliche Regelungen an der Erfüllung eines vorgegebenen Organisationsziels mitwirken. Softwareagenten benötigten Zugriff auf Ressourcen um einerseits bestimmte Dienste anbieten (z.B. Datenbank-Zugriff) aber auch um ihre eigene Ausführung sicherstellen zu können (z.B. Hardwareressourcen). Softwareagenten können die ihnen zur Verfügung stehenden Ressourcen nutzen um einer Multiagenten-Organisation im Rahmen einer Mitgliedschaft Dienste zur Verfügung zu stellen. Die Erbringung von Diensten konsumiert stets einen Teil der einem Softwareagenten zur Verfügung stehenden Ressourcen. Softwareagenten werden daher einer Multiagenten-Organisation Dienste nur gegen eine entsprechende Kompensation zur Verfügung stellen. Der Beitritt eines Softwareagenten zu einer Multiagenten-Organisation ist stets das Ergebnis von Beitrittsverhandlungen zwischen diesen beiden Akteuren, in denen neben den bereitzustellenden Diensten und der zu zahlenden Kompensation, insbesondere die Dienstgüte verhandelt wird. Softwareagenten können dabei Mitglied in mehreren Multiagenten-Organisationen sein. Jeder Softwareagent hat hierbei zu entscheiden, ob bzw. welcher Multiagenten-Organisation er beitritt und in welchem Umfang er die verfügbaren Ressourcen hierfür einsetzt. Dabei hat er bereits bestehende Mitgliedschaften in anderen Multiagenten-Organisationen, für die der Softwareagent bereits Dienste bereitstellt und somit Ressourcen auslastet, bei der Beitrittsentscheidung mit zu berücksichtigen. Hieraus lässt sich folgende Forschungsfrage ableiten: Wie sind Entscheidungsverfahren auszugestalten, die es Softwareagenten ermöglichen, nutzenmaximierende Beitrittsentscheidungen zu Multiagenten-Organisationen zu treffen? Diese Arbeit präsentiert ein Verfahren zur Optimierung von Beitrittsentscheidungen von Softwareagenten zu Multiagenten-Organisationen. Das entwickelte Verfahren basiert auf Ansätzen des Revenue Management als Teilbereich des Operations Research. Die in der Literatur vorhandenen Verfahren des Revenue Management sind dabei nicht in der Lage, die Gegebenheiten von Beitritts-entscheidungen von Softwareagenten abzubilden. Das entwickelte Revenue Management-basierte Modell der Beitrittsentscheidung versetzt Softwareagenten in die Lage Mitgliedschaften in Multiagenten-Organisationen zu bewerten, deren Dauer a-priori unbekannt ist, und potentielle Mitgliedschaften anhand verschiedener Dienstgüteklassen abzugrenzen. Das entwickelte Verfahren nutzt die auf dieser Basis vorhandenen Möglichkeiten der Optimierung von Beitritts¬entscheidungen, greift den Ansatz von Ressourcen-bezogenen Reservationspreisen (so genannten Bid-Prices) aus dem Revenue Management auf und passt diesen auf die Gegebenheit von Beitritts¬entscheidungen von Softwareagenten an. Das entwickelte Verfahren wird durch ein Simulationsexperiment auf ihre Wirksamkeit und die hierfür notwendigen Bedingungen hin evaluiert. Zur Erreichung dieser Ziele wird ein Referenz- Entscheidungsverfahren herangezogen und verschiedene Parameter der Simulation jeweils paarweise variiert. In der Mehrzahl der untersuchten Parameterkonstellationen erzielt das entwickelte Verfahren eine Steigerung der erwirtschafteten Kompensation. Softwareagenten, die in einer Domäne Dienste anbieten, in der diese Parameterkonstellationen vorzufinden sind, werden durch die Anwendung des Verfahrens in die Lage versetzt, höhere Kompensationen durch Mitgliedschaften in Multiagenten-Organisationen zu erzielen als mit dem Referenz-Entscheidungsverfahren. Sind dem Softwareagenten einzelne Parameter a-priori nicht bekannt, kann mit Hilfe dieser simulativen Evaluation bereits das Risiko des Einsatzes des Verfahrens abgeschätzt werden. Das entwickelte Verfahren konnte jedoch nicht für alle Parameterkonstellationen einen Vorteil erwirtschaften, so dass für die Anwendung zwei wesentliche Voraussetzungen zu beachten sind: (1) Differenzierungsmöglichkeiten. Grundvoraussetzung für die Anwendung des Verfahrens ist die Möglichkeit der Differenzierung und den damit verbundenen Unterschieden in der Höhe der erzielten Kompensation bei gleichem Ressourceneinsatz. Diese Differenzierung kann durch verschiedene Maßnahmen des Softwareagenten erreicht werden: (i) Für verschiedene Dienste mit gleichem Ressourcenbedarf werden unterschiedlich hohe Kompensationsforderungen gestellt, (ii) ein oder mehrere Dienste werden in unterschiedlichen Dienstgüteklassen angeboten, deren Kompensationen sich in ausreichendem Maße unterscheiden oder (iii) verschiedene Dienste nutzen eine unterschiedliche Menge an Ressourcen. (2) Nachfrage. Das in dieser Arbeit entwickelte Bid-Price-Verfahren kann nur durch Ablehnen von bestimmten Anfragen Vorteile gegenüber dem Referenz-Entscheidungsverfahren generieren. Voraussetzung ist somit eine entsprechende Nachfrage nach den angebotenen Diensten eines Softwareagenten und somit nach dessen Mitgliedschaft in Multiagenten-Organisationen. Steht diese Nachfrage nicht in ausreichendem Maße zur Verfügung, kann im Allgemeinen kein Vorteil gegenüber anderen Ansätzen erzielt werden. Abhängig von der individuellen Situation an angebotenen Diensten wirkt sich auch ein bestimmtes Verhältnis an nachfragenden Multiagenten-Organisationen positiv auf das Ergebnis des vorgestellten Verfahrens aus: Ist die überwiegende Zahl der Anfragen auf niederwertige Dienste oder Dienstgüteklassen ausgerichtet, jedoch auch eine ausreichend hohe Zahl an höherwertigen Anfragen vorhanden, erzielt das Verfahren deutliche Steigerungen gegenüber dem Referenz-Entscheidungsverfahren. Die voran genannten Voraussetzungen haben sich in der simulativen Evaluation als wesentlich für eine Vorteilhaftigkeit der Anwendung des entwickelten Verfahrens herausgestellt. Wenden Softwareagenten das entwickelte Verfahren für Beitrittsentscheidungen zu Multiagenten-Organisationen in Domänen an, die diese Voraussetzungen erfüllen, ist eine Steigerung der erwirtschafteten Kompensation gegenüber dem Referenz-Entscheidungsverfahren wahrscheinlich. Falls die Nachfrage kleiner als erwartet ausfällt, erzielte das Verfahren häufig die gleiche Kompensation wie das Referenz-Entscheidungsverfahren und erwirtschaftete nur in einzelnen Simulationsdurchläufen deutlich weniger, so dass selbst bei a-priori unbekannten oder unsicheren Parametern eine Anwendung des entwickelten Verfahrens möglich ist.
Mulitdimensionale Informationen im Kontext wertorientierte Unternehmensführung von Versicherern
(2017) Trautinger, Max-Josef; Schiller, Jörg
The cumulative dissertation analyzes how multi-dimensional information influences customer behavior and how insurers can use that information efficiently as a key factor in customer interaction. Information per se is multilayered and can be multidimensional. Multidimensional information in this context is understood as known or generally available information about customers, which should help in the interaction between the insurer and the customer to fulfill the customer expectations. As an additional research question, this dissertation analyzes how insurers can use the information economically profitably and generate added value. Provided that information can be used effectively value orientation can be generated. For example, having data in a pure form does not add value to insurers. If this information can at least be used to satisfy customer expectations, it can be assumed that customers want to use offered services and are disposed to a higher willingness to pay. In three analyzes this question is taken up separately and discussed. Analysis 1: In a competitive insurance market, claims settlement is a central task of insurers. Customers indicate after an event of loss specific expectations and further the adept service is of customers point of view a ‘moment of truth’. Insurers may align their claims settlement and optimise it. This paper analyse which determinants influence the customer satisfaction. The hypotheses were shown in a model and discussed by the author. Also, the hypotheses evaluated on the basis of empirical data which is derived from a set of interviews by a german insurer. The results of the analysis show variables which can be influenced in order to improve the customer satisfaction. Analysis 2: Customer behavior is managed by customer satisfaction in two dimensions: Insurer can profit by a higher customer loyalty und in addition, by a sensitive price behavior of customers. The findings of moderating effects are mean considered and thus, customer satisfaction is a too strong indicator of economic success in established concepts. To manage an insurance company effective, it is a good advice to implement a model that is specific for each company. This model should respect the heterogeneous factors of influence due to customer satisfaction by multidimensional instruments. Hence, insurer may identify drivers of service and work with analysis of correlations to describe the coherence between customer satisfaction and economic success exactly. The alignment for customer satisfaction is worth for traditional insurance companies, but only, if customer satisfaction is understood as an economic valued management that is culturally based in the firm. Manager should account for this suggestion to follow a sustainable story in a saturated competitive environment. Analysis 3: In this analysis we analyze in a project selection effects in the German market for private complementary long-term care insurance contracts (CompLTCI) within a static and dynamic framework. Using data on more than 98,000 individuals from a German insurance company, we provide evidence that advantageous selection is dominating in this market, with respect to both the decision to buy a CompLTCI policy and the decision about the extent of CompLTCI coverage. We identify occupational status, residential location and the holding of further supplementary health insurance policies as unused observables contributing to selection effects in this market. Our results suggest that non-linearities in the relationship of potential sources of selection to insurance coverage and risk should be considered. A panel data analysis shows that an increase in health insurance payouts is positively correlated with the uptake of CompLTCI, while a decrease in those costs is positively associated with the lapse of CompLTCI. In addition, we find that people in financial distress and of lower socioeconomic status are more likely to let their CompLTCI policies lapse.
Essays in health economics
(2018) Kaiser, Micha; Sousa-Poza, Alfonso
In economic theory a lot of attention is given to the understanding and modelling of consumption decisions of individuals. Usually, most models assume that individuals consume different markets goods and maximize their utility with respect to certain constraints. These constraints can be of various kinds. Besides monetary constraints health related constraints are vitally important during the maximization process of individuals. In such a paradigm, individuals would therefore benefit indirectly from being in a good health state, since this would imply that they are less constrained and could therefore shift their individual utility to a higher level. Moreover, health can also be treated as a good itself. Such an approach would assign a direct effect of different health states to an individuals utility rather than incorporating health states by including them as a source for binding constraints. Apart from the different strategies in modelling the consumption decisions, both ways of thinking have in common that the achievement as well as the maintenance of a good health state is – to some extent - a necessary condition to foster the utility maximization process. Additionally, health outcomes of individuals are highly sensitive to economic circumstances and different policy interventions. For instance, a change in the individuals income will lead to an adjustment of the optimal consumption decision and therefore also to an adjustment of the health outcome (either in a direct or indirect way). Therefore a profound understanding of the impact of changes in economic and political processes helps to assess their effects on the health outcomes of individuals. Hence, this thesis investigates the impact of different economic factors and policy interventions on health. In particular, the thesis contributes to the literature in the following way: Chapter two uses 22 years of data from the German Socio-Economic Panel and information on plant closures to investigate the effects of unemployment on four indicators of unhealthy lifestyles: diet, alcohol consumption, smoking, and (a lack of) physical activity. The main goal is to assess possible causal effects of unemployment on risky behaviors. In fact, in contrast to much of the existing literature the empirical identification strategy used in this analysis, is able to clearly identify exogenous effect and therefore avoids endogeneity, which may result from reversed causality. The main results provide little evidence that unemployment gives rise to unhealthy lifestyles. Chapter three evaluates the relation between preschool care and the well-being of children and adolescents in Germany by using data from the German Health Interview and Examination Survey of Children and Adolescents. Analyzing this relationship is important to provide conclusive knowledge for parents as well as policy-makers due to several reasons. While parents are interested in providing the best health outcomes for their children, policy-makers need to balance a possible trade-off between economic as well as social costs and benefits related to preschool care. Additionally, the chapter examines differences in outcomes based on child socioeconomic background by focusing on the heterogeneous effects for migrant children. The findings suggest that children who have experienced child care have a slightly lower well-being overall. For migrant children, however, the outcomes indicate a positive relation. The fourth chapter analyzes how a nationwide population-based skin cancer screening program (SCS) implemented in Germany in 2008 has impacted the number of hospital discharges following malignant skin neoplasm diagnosis and the malignant melanoma mortality rate per 100,000 inhabitants. Therefore, panel data from the Eurostat database, which covers subregions in 22 European countries is analyzed for the years 2000-2013. By using fixed-effects methods, the causal relationship between the skin cancer screening program and the change in diagnosis and mortality rates are identified and a policy implication is derived. While the results indicate that Germany’s nationwide SCS program is effective in terms of a higher diagnosis rate for malignant skin neoplasms and thus may contribute to an improvement in the early detection of skin cancer, there is no significant influence on the melanoma mortality rate. Chapter five analyzes how closely different income measures conform to Benford’s law, a mathematical predictor of probable first digit distribution across many sets of numbers. Because Benford’s law can be used to test data set reliability, a Benford analysis is applied to assess the quality of six widely used health related survey data sets. This is of particularly importance for health economists, since the majority of empirical work in this field relies on information from survey data. The findings indicate that although income generally obeys Benford’s law, almost all the data sets show substantial discrepancies from it, which can be interpreted as a strong indicator of reliability issues in the survey data. This result is confirmed by a simulation, which demonstrates that household level income data do not manifest the same poor performance as individual level data. This finding implies that researchers should focus on household level characteristics whenever possible to reduce observation errors.
Selektivverträge in der medizinischen Versorgung
(2017) Arnegger, Silke; Ernst, Christian
In the past fifteen years, Germany has introduced several types of medical care and cooperation opportunities between actors in the healthcare market. The gatekeeper model known as Hausarztzentrierte Versorgung (HZV) is a primary physician model and is an example of selective or individual contracting that is now possible between physicians in private practice and health insurance companies. It is also an example of new policy instruments intended to increase competition in the healthcare system (e.g. between insurance companies, amongst physicians in private practice). Increased competition should lead to improvements in the quality of patient care and economic efficiencies in the provision of that care. The latter is an especially important goal in light of the fact that there are a growing number of patients with chronic diseases. Selective medical care contracts like the HZV are situated at this pivot point. Going forward, German health insurance companies and other healthcare market actors – in particular, physicians in private practice – are allowed to enter into individual contracts for the provision of medical care to a group of patients. For this purpose, physicians specializing in a particular field mandate their professional associations to negotiate contracts. Thereafter physicians who want to participate in these contracts can offer the applicable provisions to their patients. Previously, all insurance companies and all registered doctors in private practice were required to enter into collective agreements. Contracts like the HZV mean it should now be possible to study the individual patient care models of different health insurance companies and offer medical care that is better tailored to patients. Additionally, these contracts should encourage communication amongst different actors in the healthcare system and incentivize their behaviour to generate efficiencies. This empirical study aims to explain whether the HZV, namely the selective contracts for primary care physicians in the state of Baden-Württemberg, contain the right incentives for participating doctors (agents) to produce efficient results for the insurance companies with which they have contracted (principals). Data on the quality and efficiency of care provided under these contracts is compared to data on their financial impact on participating doctors. New Institutional Economics inform the theoretical framework used in this study. Its theories of social contract, especially agency, and transaction costs play a central role in interpreting and analysing the data collected. Many studies of selective contracting in the field of healthcare economics focus on legal issues arising from actual and proposed changes to the law. By providing an empirical healthcare oriented economic account of such contracts for primary care physicians in Germany, this study supplements that literature with data and analysis that has been lacking on this important development.
Electronic service allocation with private quality information
(2017) Widmer, Tobias; Kirn, Stefan
The efficient allocation of electronic services is a complex business problem. Customers demand electronic services from service providers who supply these services at a specified quality of service (QoS). Electronic marketplaces provide a platform on which multiple customers and multiple providers negotiate the allocation of electronic services. Such marketplaces might be administrated by government authorities or large corporations who aim at a socially optimal allocation. This research addresses the allocation problem for electronic services with private quality information from a mechanism design perspective. By assigning specific reservation functions, multiple customers and multiple providers enunciate their preferences for these services. Once all demands and offers for electronic services are submitted, the mechanism determines an allocation that maximizes the sum of the aggregated preferences. However, the design of such mechanisms is difficult because of the following requirements: (1) Double-sided competition: Multiple competitive customers and multiple competitive providers must be matched together appropriately to generate maximal surplus, (2) QoS-awareness: The QoS desired by customers and the QoS offered by service providers must be internalized in the allocation mechanism, (3) private information: The mechanism must facilitate the allocation of electronic services for which any QoS information is unknown, (4) incentive compatibility: The mechanism has to provide adequate incentives to strategic individuals in order to ensure truthful bidding, (5) individual rationality: The participation decision in the mechanism must be voluntarily to all bidders, (6) budget balance: The mechanism must omit any independent intermediary in order to facilitate distributed decision-making among the participants, (7) optimality: The ultimate objective of the mechanism is to achieve an outcome that is optimal from a social welfare perspective. Standard impossibility theorems from mechanism design theory assert that meeting these requirements simultaneously is not attainable. In particular, ex post optimality cannot be attained when incentive compatibility, individual rationality, and budget balance are required as well. Therefore, the mechanism designer must decide about a viable tradeoff of these requirements. One possible compromise in the presence of privately known QoS is to derive a second-best mechanism that satisfies incentive compatibility, individual rationality, and budget balance. The outcome of such second-best mechanisms can be used to estimate the efficiency loss that must be tolerated in comparison to the first-best outcome. The objectives of this research are to (1) develop a second-best mechanism for allocating electronic services with private quality information and (2) study its efficiency properties in a set of simulation experiments to demonstrate its usefulness. All experiments imply that the asymptotic efficiency of the second-best mechanism is bounded away from 100% even for large markets. This finding is related to the economic concept of informational smallness, which is defined as the incremental impact of an participants QoS on the demand of an electronic service. In the proposed model, each provider offers a service of distinct QoS, and each customer demands a service of distinct QoS. It is this feature of differentiated service quality that prevents the participants from becoming informationally small as the market becomes large. If each participant’s private information about QoS follows the uniform distribution, the mechanism must tolerate an efficiency loss of more than 31% for an increasing number of customers and providers. In contrast, if private quality information is normally distributed among participants, this research finds that the mechanisms asymptotic inefficiency can be reduced to about 7% as the market size increases on both sides. With asymmetric, beta-distributed QoS, the mechanism arrives at an asymptotic efficiency of more than 91%. These findings are crucial to social planners because in designing service allocation with double-sided competition, they can obtain an accurate estimation of potential efficiency losses that arise from asymmetric information about QoS. On the other hand, the social planner can ensure that every allocation decision is made by the participants only. Hence, the emerging mechanism implementation eludes the need for an external, independent decision maker.
Investor sentiment in blogs : design of a classifier and validation by a portfolio simulation
(2016) Klein, Achim; Kirn, Stefan
How can investment recommendations available on the web significantly improve stock selection? This dissertation shows how online investment recommendations can automatically be analyzed, aggregated, and used to achieve a return above the market’s. To this respect, it is crucial to understand how investment recommendations affect returns. Therefore, the dissertation examines the effects of direct and indirect investment recommendations from blogs in the form of investor sentiments (i.e., opinions) on the expected development of stock prices. Blogs have made it possible for everyone to publish articles on the web. The studied blog platforms Seekingalpha and Blogspot host a wealth of semi-professional stock analyses, investor opinions, company rumors, and stock recommendations. The dissertation’s study uses about 77,000 articles from Seekingalpha and about 198,000 articles from Blogspot over a five-year period (2007-2011). A novel text classification method is developed for the automatic classification of blog articles in a positive vs. negative sentiment. To achieve a high classification accuracy, experiments were carried out to configure this method. The text classification method uses machine learning techniques, which learn from manually classified articles from a novel corpus. Using behavioral finance theory, hypotheses are developed about the effects of investor sentiments on a portfolios returns. To test these hypotheses, a monthly selection of stocks of the Dow Jones Industrial Average into a portfolio was simulated (i.e., backtested). The selection is made by means of the ranking of the monthly aggregated overall sentiment of all articles regarding a specific stock. The results show that a return above the market’s can be achieved with aggregated investor sentiments from the Seekingalpha platform. In most cases, the achieved return exceeds the return of a momentum portfolio based solely on past returns. For the platform Blogspot, results are weaker. Overall, it seems advisable for investors to select a small number of stocks based on the most positive and most negative monthly investor sentiments from professional blogs.

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