Prioritätensetzung in der Agrarforschung ist ein komplexes Entscheidungsproblem angesichts der Unsicherheit in der Abschätzung der erwarteten Wirkungen von Forschung und Technologien und den vielfältigen sozialen und wirtschaftlichen Zielen, die mit der Generierung von Wissen und neuen Technologien in landwirtschaftlichen Forschungsinstitutionen in Entwicklungsländern verbunden sind. Diese Arbeit versucht durch die Anwendung von formalen und quantitativen Evaluierungs- und Entscheidungsmethoden mit der besonderen Berücksichtigung von Unsicherheit und multiplen Zielen einen Beitrag zur Methodenverbesserung in der Prioritätensetzung zu leisten. Zur Darstellung dieser Methoden wurde als Fallstudie das nationale Milchviehforschungsprogramm des "Kenyan Agricultural Research Institute" (KARI) ausgewählt. Gegenstand der Analyse sind 19 geplante Forschungsprojekte, die anhand eines stochastischen Evaluierungsansatzes ("Economic Surplus" und Monte Carlo Simulation) hinsichtlich ihrer ökonomischen Wirkungen auf den kenianischen Milchmarkt untersucht wurden. Die Evaluierungsergebnisse der Forschungsprojekte und anschließende Bewertung anhand verschiedener stochastischer Dominanztests zeigen, daß die Ableitung einer klaren Präferenzstruktur und Rangordnung innerhalb der Projekte nach ökonomischen Kriterien, z.B. Gegenwartswert und Kosten-Nutzenrelation, in vielen Fällen nicht möglich ist, sondern vielmehr von den unterstellten Risikopräferenzen abhängt. Dies bedeutet, daß aus der Sicht eines Planers eine differenzierte und vorsichtige Interpretation und Beratung des Forschungsmanagements vorzunehmen ist. Dies steht im Gegensatz zu einer deterministischen Investitionsanalyse. Mehrere mathematische Programmierungsmodelle wurden zur Analyse von multiplen Zielen, der Untersuchung der Wirkungen von Verteilungsaspekten und unterschiedlicher Risikopräferenzen auf die Zusammensetzung eines optimalen Forschungsportfolios entwickelt und angewandt. Obwohl in den meisten Fällen eine Änderung der Risikoeinstellung auch eine Änderung des optimalen Portfolios bewirken würde, sind die ökonomischen Unterschiede gemessen am Gegenwartswert der alternativen Portfolios unbedeutend. Die Analyse der Zielkonflikte zwischen Effizienz- und Verteilungsziel wurde unter zwei unterschiedlichen Blickwinkeln für das Verteilungsziel untersucht: zum einen als räumliche und regionale Allokation des Forschungsnutzens, und zum anderen zwischen kenianischen Konsumenten und Produzenten von Milch. Aus den Modellergebnissen wird deutlich, daß eine spezielle Förderung von Produzenten- sowie Konsumenteninteressen nur beschränkt möglich ist, d.h. die jeweiligen Planungsoptionen nur geringe Umverteilungswirkungen erzielen. Ganz anders stellt sich die Situation bei einer regionalen Differenzierung dar. Dort würden je nach relativer Bedeutung einzelner Regionen starke Umverteilungswirkungen in den regionalen Einkommen auftreten. Allerdings sind diese Optionen im Vergleich zu einer "neutralen", d.h. regional indifferenten Ausrichtung mit großen Effizienzverlusten verbunden. / Priority setting in agricultural research is a complex decision making problem due to the inherent uncertainty surrounding the impact of research activities and the multiple social and economic research objectives under which research institutions in developing countries have to operate. This study attempts to apply formal and quantitative evaluation and decision making methods for a more rigorous and explicit analysis of the uncertainty and multiple research objectives. These methods are illustrated by applying them to a priority setting exercise for the National Dairy Research Program of the Kenyan Agricultural Research Institute (KARI) conducted in 1996. A set of 19 planned dairy research projects was proposed and specified by KARI scientists and the economic impact assessed based on a stochastic evaluation framework using economic surplus methods and Monte Carlo simulation. Results show that comparing these projects by stochastic dominance criteria with respect to the expected net present value and cost-benefit ratio the final rank order is very much subject to assumed risk preferences of the decision- makers. Thus, decision advice on the type of prioritised projects for implementation and fund raising is much less clear-cut than a deterministic evaluation would suggest. Mathematical programming techniques were applied to analyse the trade-off between multiple research objectives, to examine the distributional consequences of research, and to explore how different risk strategies (from risk aversion to risk proneness) would affect the selection of a optimal research portfolio from the planned dairy research projects. Although risk has a strong bearing on the composition of a research portfolio for various different funding levels the economic implications are not significant in terms of net present value. In a Multiple-objective programming framework the trade-off between efficiency and equity was examined. Equity concern was looked at two different angles: first, by a spatial distribution of the research benefits, and second by the distributions among consumer and producer groups. Results show a limited scope of directing the dairy research plan either for the sake of consumers or producers while the scope of targeting different production zones in Kenya is much larger although the trade-offs in terms of foregone welfare between different zones are very pronounced.

Abiotic stresses such as salinity and phosphorous (P) deficiency are major yield-limiting factors for rice, particularly on marginal lands. Marker-aided backcrossing (MAB), enabled by advances in genomics and molecular mapping in recent years, is said to be a more precise, time-saving, and cost-effective way to develop rice varieties that can withstand these abiotic stresses than conventional breeding. The study employs the economic surplus approach to measure the benefits of MAB for salinity tolerance in rice for Bangladesh, India, Indonesia, and Philippines, and for rice with tolerance to P-deficient soils in Indonesia. At a 5% discount rate, the benefits over 15 years of planting salt-tolerant varieties amount to $226.9 million in the Philippines, $3.666 billion in Bangladesh, $4.848 billion in India, and $895.7 million in Indonesia. The gains from growing varieties that can withstand P deficient soils in Indonesia amount to $2.070 billion. The incremental benefits from completing the salt-tolerant and P-deficient tolerant breeding cycles 2 years earlier are $340.5 million in Bangladesh and $192.1 in Indonesia, respectively. In India, $227.0 million is gained even if MAB develops salt-tolerant varieties just a year earlier. The additional gains from completing the salt-tolerant rice breeding cycle 4 years earlier are $40.3 million in the Philippines and $158.9 in Indonesia. In general, the gains from saline- (Bangladesh, Indonesia, Philippines) and P-deficient (Indonesia) tolerant rice are reduced by 5%, 9%, 14%, and 18% when MAB breeding cycle is delayed by one, two, three, and four years, respectively. In India, there is 3%, 7%, 10%, and 13% loss in benefits from salt-tolerant rice for every additional year of delay in the MAB breeding cycle. / Master of Science

Cooperation-88 (C88) is a late blight resistant potato variety that was formally released in China in 2001 and has become popular in China's Yunnan Province. The International Potato Center (CIP) and Yunnan Normal University collaborated to produce the variety, which is one of CIP's most successful varieties. C88 is popular due to its high quality and taste, and it is used commonly in China's expanding potato chip processing market. The purpose of this study is to examine adoption of C88 in the Yunnan Province, its value chain, and economic impacts. The analysis indicates that C88 is still popular with 16.8% of the potato area in Yunnan devoted to this variety in late spring 2015. To examine factors affecting household decisions to adopt and the intensity of their adoption, village adoption, household adoption, and household intensity of adoption were assessed. A village's proximity to a metropolitan county was the most important factor explaining adoption and intensity of adoption. Households in villages closer to a metropolitan county disadopted at higher rates than those farther away. To quantify the economic benefits of C88 adoption, an economic surplus analysis was conducted. Total surplus changes ranged from $2 to 3 billion indicating significant economic benefits to consumers and producers in Yunnan. / Master of Science / Cooperation-88 (C88) is a popular late blight resistant potato variety that was released to the Yunnan Province of China in 2001. Late blight is the disease responsible for the Great Potato Famine in Ireland. The International Potato Center (CIP) and Yunnan Normal University collaborated to produce the variety, and C88 is one of CIP’s most successful varieties. C88 is popular due to its high quality and taste, and it is used commonly in China’s potato chip processing market. The purpose of this study is to examine the number and types of people who adopted C88 in the Yunnan Province, provide an understanding of the process from farm to consumer, and to determine the economic impacts of the variety. A major finding of the study is that C88 remains popular in Yunnan as of spring 2015. To study the households that grew C88 during the spring 2015 season, statistical analysis was conducted with the focus on what household traits influence the number of surveyed households who grow C88 in a village, whether a household grows C88, and the number of hectares under C88. A village’s proximity to a metropolitan county was the most important factor explaining whether a household adopted the variety and the number of hectares. Households in villages closer to a metropolitan county stopped growing C88 at higher rates than those farther away. To quantify economic benefits, a supply and demand analysis of potatoes in Yunnan was conducted, which indicated significant economic benefits to consumers and producers in Yunnan.

With shifting preferences of consumers towards healthier food, organic food demand has been on the rise for the past two decades. This increased demand has created an opportunity for farmers to shift from conventional to organic production. However, there are risks and uncertainties associated with organic farming. The management of an organic farm in the absence of organic-based disease and pest suppressing strategies constrains farmers from adopting organic vegetable production. The use of cover crops to control soil-borne diseases and suppress weeds and other pests has increased because of its sustainable and environmental friendly nature. This study of the economic impact of the cover crops on organic tomato production in the three states Ohio, New York, and Maryland showed mixed results. In Maryland, mixed forage radish and hairy vetch was projected to have a net present value over 15 years that was $1.53 million higher than single species hairy vetch, assuming maximum adoption level of 50 percent. In New York, mixed rye and turnip gave the higher return with a net present value of $2.61 million. In Ohio, the highest projected return was from mixed hay compared to hairy vetch with a net present value of $3.12 million when used without adding compost amendments. In Maryland and New York when bare ground was also used as a control, only mixed forage radish and hairy vetch in Maryland produced better returns compared to bare ground. A probit regression assessing the factors affecting the decision to adopt mixed species green manure technology indicated that farmer experiences in organic production, farmer age, access to the internet access, and farmers’ perceptions about the benefits of using mixed species green manures were significant factors. Each variables and factors except age had a positive influence. Similarly, probit results for microbial inoculants indicated that education, gender, and access to the internet were significant determinants, and had a negative effect on the probability of adoption. Access to the internet was significant for both mixed species green manures and microbial inoculants but with opposite sign, positive for mixed species green manures and negative for microbial inoculants. / Master of Science

The accelerating pace of growth of aquaculture in sub-Saharan Africa has received much positive appraisal because of the potential of the industry to contribute to economic development and food security by providing jobs and animal protein. Adoption of best management practices (BMPs) holds the potential to ameliorate the related environmental impacts of aquaculture, such as in the amounts of nutrients and sediment that will enter natural water bodies from earthen pond effluents. The goals of this study were to characterize adoption of aquaculture BMPs on small-scale, pond-based farms in Ghana, and to assess selected economic, social, and environmental outcomes of BMP adoption. Two BMPs: 1) water reuse, and 2) commercial floating feeds, were investigated for adoption by pond-based fish farmers in Ghana. I conducted my study in Ghana using on-farm experiments involving intensive monitoring of water quality and growth of Nile tilapia (Oreochromis niloticus) over two production cycles. Additionally, I administered a baseline survey to 393 (and a follow-up survey to 160) fish farmers. I determined the best model for modelling farmed Nile tilapia growth with multi-model inference based on Akaike information criterion (AIC), the profitability of adopting BMPs with stochastic enterprise budgets and, social welfare impact with the Economic-Surplus model. I used a Markov model to predict the equilibrium rate of adoption of the two BMPs and determined the impact of BMP adoption on the reduction of pollutant loading with the Minimum-Data method of the Tradeoffs Analysis (TOA-MD). My results showed that the logistic model is a better alternative to the von Bertalanffy model for modelling the growth of Oreochromis niloticus under pond aquaculture conditions. There were no significant differences in fish weight between the water re-use BMP and the use of new water. Adoption of the commercial floating feed BMP resulted in a 100% increase in fish final weight and yield, and in higher profitability, compared to the sinking feed type. Probability of making a profit was highest (72%) in the scenario with commercial feed and self-financing. Net present values (NPV) of about US$ 11 million and US$ 375 million could be obtained from the adoption of commercial floating feed and Genetically-Improved Farm Tilapia (GIFT) strain, respectively, in Ghana. Hence, any innovation that has a significant impact on fish yield also will have a significant impact on mean NPV and social welfare. However, I identified a number of potential negative ecological and genetic impacts exist from introducing the GIFT strain into Africa from Asia. Although considered low-intensity production systems, nutrients and solids in study ponds were found to be higher than levels expected in intensive culture ponds by wide margins. Pond water quality was significantly higher with commercial floating feed. The water-reuse BMP also prevented pollutants from leaving ponds altogether for the number of cycles for which pond water was reused, especially if associated BMPs such as rainfall capture and avoidance of water exchange are observed. Significant reductions in the loading of all water quality variables (nitrogen, phosphorus, solids, and BOD5) could be achieved with the adoption of the recommended feed type in Ghana. Adoption of the water reuse BMP has the potential to cause pollution reductions of 200% - 3,200% above that from the floating feed BMP. The strongest influence on the combined adoption of these BMPs were from : farmer's awareness of the feed BMP, perceived necessity and relative profitability of the water reuse BMP, and farmer's years of experience. A combination of central media (workshops), demonstrations, and lateral diffusion was found to be the most effective channel for disseminating these BMPs. Maximum adoption rate of the feed BMPs was estimated to be 38% - 58%. Also, US$ 6,000/year and US$12,000/year need to be paid per 0.6 ha pond surface area to push adoption of the feed BMP to 50% and 70%, respectively. Hence, to ensure the successful adoption of aquaculture BMPs, I recommend that regular well-planned workshops be organized to create awareness and a conducive atmosphere to target farmers at multiple stages of the innovation decision process. Incentives and effective dissemination will encourage the adoption of these and other environmental BMPs. Feed costs need to be lowered in order to encourage the adoption of commercial floating feed in Ghana. Future analyses could quantify the differences in production costs between using the two water types, to reveal the possible higher relative profitability of pond water reuse over draining ponds after each production cycle. Also, African governments are advised to commission rigorous baseline and ecological risk analyses before adoption of the GIFT strain. Improvements in management practices and infrastructure could increase the yield and profitability of the local strains even if genetically-improved strains are not introduced. / Ph. D.

過去電力事業為了滿足電力用戶之需求，對於新電源之開發不遺餘力。然而由於電力事業近年來在供給面規劃屢遭當地居民抗爭而受阻，因而晚近轉而強調用戶需求面之管理。 本文針對台電公司現行需求面管理之「用戶計劃性減少用電措施」四種方案進行研析。首先設定簡化條件，將四種方案予以模型化，利用經濟剩餘模型，進行邊際分析，探討台電公司提供優惠之折扣比例及電力的價格需求彈性如何參與用戶抑低容量以及消費者剩餘、生產者剩餘分配之效果。分析結果顯示：「計劃性（二）」抑低用戶負載容量最高，且參與用戶之消費者剩餘最多；「計劃性（一）」抑低用戶負載容量最低，且參與用戶之消費者剩餘最少。另一方面，若從電力公司之視角觀之，「計劃性（二）」之生產者剩餘最低，而「計劃性（一）」之生產者剩餘最高。 經濟剩餘模型分析中，由於未能充分考慮供需雙方之潛在成本與效益，因此實務上之解釋能力有其侷限之處。基於上述緣由，本文接著藉由成本效益分析，將方案實施之潛在成本與效益納入考量，分別從參與用戶之角度進行參與者檢定（Participant Cost Test, PCT）以及從電力公司之角度進行公用事業成本檢定（Utility Cost Test, UCT），以檢視不同方案在不同觀點下之績效表現。成本效益分析結果顯示：在PCT檢定下，「計劃性（四）」參與用戶之益本比最高，「計劃性（二）」參與用戶之益本比最低。而在UCT檢定下，「計劃性（一）」電力公司益本比最高，「計劃性（四）」電力公司益本比最低。將成本效益分析與經濟剩餘模型比較後可發現，用戶抑低容量高的方案對於電力公司而言未必最有利。 最後，為進一步探討關鍵變數變動造成不同方案間成本效益值之影響，因此進行敏感度分析。敏感度分析的結果顯示：若電力公司為吸引用戶而提高誘因，增加各方案給予用戶優惠折扣之比例，以參與用戶角度而言，「計劃性（四）」參與者檢定之益本比提高幅度最大；以電力公司角度而言，「計劃性（四）」公用事業成本檢定之益本比降低幅度最大。若電力公司提高參與用戶每次抑低用電負載之時數，以參與用戶角度而言，「計劃性（四）」參與者檢定之益本比降低幅度最大；以電力公司角度而言，「計劃性（四）」之公用事業成本檢定益本比提高幅度最大。 / In order to meet the users’ demand of electricity, the electric power utility spared no effort to develop the new power plant in the past. However, in recent years, the electric power utility have been hampered by local residents on supply-side planning, thus more emphasize is being put on users’ demand-side management（DSM）. This paper aims to analyze four projects of Taipower’s existing demand-side management of “incentive plan for customers’ scheduled load curtailment program”. First, we set several simplified conditions for modeling the projects. By using the economic surplus model and conducting the marginal analysis, the impact from the discount incentive provided by the utility and the elasticity of electricity price demand is explored－on participants’ load capacity reduction and the distribution of consumer surplus and producer surplus. The results of economic surplus model showed "project 2" curtails the maximum load capacity and with the highest consumer surplus; "project 1" curtails the minimum load capacity and with the lowest consumer surplus. On the other hand, in the Taipower's point of view, "project 2" provides with the lowest producer surplus while "project 1" gives the highest producer surplus. In the economic surplus model, since the potential costs and benefit were not fully considered in both supply and demand sides, several limitations exist on this model. Based on the above reasons, we utilize the cost benefit analysis, taking the potential cost and benefit into account and conducting Participant Cost Test（PCT） from the participants’ perspective and Utility Cost Test（UCT）from the utility’s perspective to examine the performance under different 4 DSM projects in different point of view. The results of cost benefit analysis showed that in the PCT test, the "project 4" comes up with the highest benefit cost ratio while "project 2" has the lowest cost benefit ratio. In the UCT test, the "project 1" has the highest cost benefit ratio while "project 4" came with the lowest cost benefit ratio. Comparing the cost benefit analysis with the economic surplus model, we could find that the project with the most load capacity reduction may not be the most favorable project for the utility. Finally, in order to further explore the key variables affecting the cost and benefit value in different projects, we simulated several scenarios for sensitivity analysis. The results of the sensitivity analysis showed that if the utility increases incentives to increase four projects’ ratio of discount for attracting participant, in the participants’ perspective, "project 4" would have the most changed rate of cost benefit ratio（increase）; in the utility's perspective, "project 4" would have the highest adjusted rate of cost benefit ratio（decrease）. If the utility increases the load curtailment duration each time, in the participants’ perspective, "project4" would have the highest adjusted rate of cost benefit ratio（decrease） ; in the utility’s perspective, " project4 " would have the highest adjusted rate of cost benefit ratio（increase）.

Landwirtschaftliche Systeme müssen sich immerfort an Druckfaktoren wie Klimawandel und Bevölkerungswachstum anpassen. Hierbei spielt die genetische Vielfalt von Pflanzen eine wichtige Rolle, da diese für die Sicherung der Ernährung und des Einkommens von entscheidender Bedeutung ist. Dennoch wird der wirtschaftliche Wert pflanzengenetischer Ressourcen selten untersucht. Um diese Forschungslücke zu schließen, werden in dieser Arbeit drei Bewertungen vorgestellt, welche die wirtschaftlichen Werte pflanzengenetischer Ressourcen untersuchen. Im Rahmen dieser Dissertation werden zwei verschiedene Agrarsystemen analysiert. Diese unterscheiden sich hinsichtlich des Klimas, der agrarökologischen Bedingungen, der landwirtschaftlichen Praxis, der politischen und ökonomischen Rahmenbedingungen sowie der soziokulturellen Verankerung der Kulturart. Die ersten beiden Analysen befassen sich mit der Züchtung und Produktion von Winterweizen in Deutschland. Charakterisiert sind diese durch ein gemäßigtes Klima und intensive Anbaubedingungen. In diesem System überwiegen moderne Sorten, die in einem formalisierten Züchtungsprozess entstanden sind. Es werden die folgenden Forschungsfragen beantwortet: 1) Was ist der ökonomische Wert, der durch den Austausch von Zuchtmaterial entsteht? und 2) Wie hoch ist der mikroökonomische Wert von Resistenzzüchtung? In der dritten Analyse wird ein weiteres Agrarsystem vorgestellt: Die Andenlandwirtschaft, wo im Hochland unter extensiven Bedingungen eine Vielzahl von Kartoffellandrassen angebaut wird. Dort wird folgende Frage analysiert: 3) Welche Mehrwerte wurden durch die Repatriierung oder Neuverteilung von Kartoffellandrassen erzielt? Diese Analysen zeigen, dass die Verfügbarkeit, der Austausch und die Nutzung von pflanzengenetischen Ressourcen die Agrarproduktion verbessern; es entstehen sowohl sektorale, mikroökonomische als auch ernährungsbezogene und kulturelle Mehrwerte. / Agricultural systems must constantly adapt to pressuring events such as climate change and population growth to maintain and improve production processes in a sustainable manner. Thereby the genetic diversity of plants used in agriculture constitute a strategic asset. Nevertheless, their economic value is often overlooked. To fill this research gap, this thesis presents three assessments that produce more evidence on the economic value of plant genetic resources. Two very distinct agricultural systems are discussed. These differ greatly in terms of climate, agroecological conditions, farming practices, seed systems, political and economic frameworks, and the socio-cultural embeddedness of the crop in question. The first two assessments are concerned with winter wheat (Triticum aestivum) breeding and production in the temperate climate and intensive growing conditions in Germany. Modern cultivars created in a formalized breeding process prevail in this system. The following two research questions are elaborated: 1) What is the economic value of exchanging breeding material? and 2) What is the microeconomic value of resistance breeding? The third assessment presents a different agricultural system: Andean agriculture, where a wide variety of potato landraces (Solanum spp.) are grown extensively in the Peruvian highlands. In this case, the research question I investigated is: 3) What are the benefits of repatriating (i.e., redistributing) potato landraces to Andean farmers? These studies demonstrate that the availability, exchange, and adoption of plant genetic resources, which are well adapted to and culturally embedded in specific agricultural systems, improve the overall quantity and sustainability of agricultural production. These improvements can be translated into sectoral, microeconomic as well as nutritional and cultural benefits.