Masters of Science / Department of Agricultural Economics / Hikaru H. Peterson / Concerns about environmental degradation due to agriculture have gained importance as it is associated with soil erosion, health hazards, and ground water pollution. Environment-friendly land use practices have been developed to gain a wide range of environmental benefits including reduced soil erosion, reduced nutrient runoff from crop and livestock facilities, increased biodiversity preservation efforts, and restoration of wetlands and other native ecosystems. No-till is one such practice where soil erosion, nutrient runoff and environmental degradation can be reduced to a certain extent. This study evaluated the factors affecting the adoption of tillage systems in Kansas. A survey was conducted with a total of 135 participants from four different locations in the state of Kansas between August 2006 and January 2007. The adoption process was modeled as a two-step econometric models consisting of perception and adoption equations to estimate the impacts of demographic variables and farmers’ familiarity with and participation in certain conservation programs. The results for the perception models showed that the farm operators’ perceptions regarding whether BPM installation and management is unfair to producers or not and whether environmental legislation is often unfair to producers do not vary systematically across farm size, producers’ familiarity and participation in conservation programs, or other demographics considered in the study. On the other hand, their perceptions regarding how polluted their water supplies varied by their thoughts on relative profitability across various tillage practices, their primary occupation, and their familiarity with conservation programs. Specifically, the results suggested that those who regarded no-till practices to be more profitable than other tillage practices or whose primary occupation was farming-related tended to believe that ground water was not polluted, and those who were less familiar with available conservation programs tended to believe that surface waters were not polluted. The adoption model results suggested that farmers with greater operating acreage, those who perceived that no-till was more profitable than other tillage systems, and those with greater familiarity with and participation in existing conservation programs were more likely to adopt more conservation tillage systems, all else equal. Further, perceptions of fairness of environmental regulations or the level of pollution did not impact the tillage choices.

This thesis investigates the associations between crash outcomes, the existence and type of driver distraction as well as driver’s age. The crash outcomes considered in this thesis consist of the type of crash as well as the injury severity sustained by occupants involved in the crash. An ordered logit model was built to predict the likelihood of severe injuries and a multinomial model was developed to predict the likelihood that a driver will be involved in one of three common crash types: singular, angular, and rearend. In these models, various factors (e.g., weather, driver’s gender, and speeding) have been statistically controlled for, but the main focus was on the interaction of driver’s age and distraction type. The findings of this thesis have implications for policy making and prioritizing capabilities of distraction-related safety systems.

This thesis investigates the associations between crash outcomes, the existence and type of driver distraction as well as driver’s age. The crash outcomes considered in this thesis consist of the type of crash as well as the injury severity sustained by occupants involved in the crash. An ordered logit model was built to predict the likelihood of severe injuries and a multinomial model was developed to predict the likelihood that a driver will be involved in one of three common crash types: singular, angular, and rearend. In these models, various factors (e.g., weather, driver’s gender, and speeding) have been statistically controlled for, but the main focus was on the interaction of driver’s age and distraction type. The findings of this thesis have implications for policy making and prioritizing capabilities of distraction-related safety systems.

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Interaction and marginal effects are often an important concern, especially when variables are allowed to interact in a nonlinear model. In a linear model, the interaction term, representing the interaction effect, is the impact of a variable on the marginal effect of another variable. In a nonlinear model, however, the marginal effect of the interaction term is different from the interaction effect. This report provides a general derivation of both effects in a nonlinear model and a linear model to clearly illustrate the difference. These differences are then demonstrated with empirical data. The empirical study shows that the corrected interaction effect in an ordered logit or probit model is substantially different from the incorrect interaction effect produced by the margins command in Stata. Based on the correct formulas, this report verifies that the interaction effect is not the same as the marginal effect of the interaction term. Moreover, we must be careful when interpreting the nonlinear models with interaction terms in Stata or any other statistical software package. / text

This thesis uses data of more than 180 banks from CEE region to identify the main determinants of long term credit ratings assigned to these banks in period between 2010 - 2012. This is done by employing two frequently used classification methods - Multiple Discriminant Analysis and Ordered Logit Model. The main contribution lies in including explanatory variables from various areas which have impact on financial health of examined banks. Apart from standard spheres of banks' performance such as capital adequacy, asset quality or profitability we investigate relevance of macroeconomic and qualitative factors as well. Although our results suggest that all mentioned areas are relevant for credit risk and hence rating assignment process the bank specific variables, both quantitative and qualitative, still play the key role.

Travel demand Management (TDM) focuses on improving the efficiency of the transportation system through changing traveler's travel behavior rather than expanding the infrastructure. An employer based integrated TDM program generally includes strategies designed to change the commuter's travel behavior in terms of mode choice, time choice and travel frequency. Research on TDM has focused on the evaluation of the effectiveness of TDM program to report progress and find effective strategies. Another research area, identified as high-priority research need by TRB TDM innovation and research symposium 1994 [Transportation Research Circular, 1994], is to develop tools to predict the impact of TDM strategies in the future. These tools are necessary for integrating TDM into the transportation planning process and developing realistic expectations. Most previous research on TDM impact evaluation was worksite-based, retrospective, and focused on only one or more aspects of TDM strategies. That research is generally based on survey data with small sample size due to lack of detailed information on TDM programs and promotions and commuter travel behavior patterns, which cast doubts on its findings because of potential small sample bias and self-selection bias. Additionally, the worksite-based approach has several limitations that affect the accuracy and application of analysis results. Based on the Washington State Commute Trip Reduction (CTR) dataset, this dissertation focuses on analyzing the participation rates of compressed work week schedules and telecommuting for the CTR affected employees, modeling the determinants of commuter's compressed work week schedules and telecommuting choices, and analyzing the quantitative impacts of an integrated TDM program on individual commuter's mode choice. The major findings of this dissertation may have important policy implications and help TDM practitioners better understand the effectiveness of the TDM strategies in terms of person trip and vehicle trip reduction. The models developed in this dissertation may be used to evaluate the impacts of an existing TDM program. More importantly, they may be incorporated into the regional transportation model to reflect the TDM impacts in the transportation planning process.

This study uses conjoint analysis to examine the preferences of buyers for Bureau of Land Management (BLM) wild horses based on physical attributes of wild horses and individual characteristics of the buyers. Generalized ordered logit models and multinomial logit models are used to study the impact of the buyers’ demographic characteristics such as age, gender, knowledge about wild horse care, and number of wild horses previously adopted on physical attributes of the horses such as color, age, height, training status, temperament, conformation, and unique markings. Using a choice experiment, taken together, these attributes determine buyer’s preferences for a wild horse. This study reveals that characteristics of buyers have significant effects on their preferences for wild horses. Their gender, age, knowledge about wild horse care, and the number of horses previously adopted influence the importance that buyers place on physical attributes of a wild horse in their decision to purchase a wild horse.

Made available in DSpace on 2016-06-02T19:58:04Z (GMT). No. of bitstreams: 1 3674.pdf: 4771914 bytes, checksum: 5dd14583c2d833c9bb3c7f0ec784e9d4 (MD5) Previous issue date: 2011-02-21 / Universidade Federal de Minas Gerais / This research attempted to study the issue of assessing the level of service for bicycles in Brazilian cities, with the ultimate aim of developing a bicycle level of service model that can be used in medium-sized Brazilian cities. The methodology used for model development began with the identification of attributes that can be used to describe the level of service for bicycles, followed by assessing the perceptions of individuals about the importance of the attributes. Among the methods available to measure the perceptions of individuals about the roadway characteristics related to bicycle transportation, it was chosen to use simulations (video based evaluation). The video was produced through a system in which a portable video camera was attached to the bicycle stern. To compensate for the exclusion of some attributes that could not be assessed through video (such as the sensation of heat, the cost of the bicycle, the health benefits, etc) the simulation method was combined with another method of perception analysis: questionnaires formulated based on the Likert scale. Data collection was performed in a case study in the cities of São Carlos and Rio Claro (São Paulo state), in several educational facilities. In total, 451 questionnaires were administered, 60 in the city of Rio Claro and the rest of them in the city of São Carlos. The results of field study were analyzed through methods of descriptive statistics and correlations, producing the following studies: questionnaires results, classification of participants into types of cyclists, the definition of a scale of acceptability to bicycle use and classification of participants in groups, according to this scale. The Bicycle Level of Service Model was calibrated using the FLOW variable, defined as the volume of motor vehicles divided by the effective width of the road, and the level of service grades resulting from the participants evaluation. The model was validated through cross-validation methodology. The model development resulted in a graphic that can be used to determine the probability of perceived level of service for flow values found on roadways. It was considered that the study reached its primary goal, providing a Bicycle Level of Service Model that can be used in medium-sized Brazilian cities. / A presente pesquisa buscou estudar o tema da avaliação do nível de serviço para bicicletas em cidades brasileiras, com o objetivo principal de desenvolver um modelo de nível de serviço para bicicletas possível de ser utilizado em cidades brasileiras de porte médio. A metodologia utilizada para o desenvolvimento do modelo teve início com a identificação dos atributos que podem ser utilizados para descrever o nível de serviço para bicicletas, seguida pela avaliação da percepção de indivíduos sobre a importância dos atributos. Dentre os métodos disponíveis para medir a percepção dos indivíduos sobre as características viárias relacionadas ao transporte cicloviário, definiu-se pela realização de simulações, ou seja, avaliação com base em vídeo. O vídeo foi elaborado por meio de um sistema no qual uma câmera de vídeo portátil foi acoplada ao guidão da bicicleta. Para compensar a exclusão de alguns atributos que não podem ser avaliados através do vídeo (como a sensação de calor, o custo da bicicleta, os benefícios para a saúde, etc.), o método da simulação foi combinado com outro método de análise da percepção: questionários formulados com base na escala Likert. A coleta de dados foi realizada em um estudo de caso nas cidades paulistas de São Carlos e Rio Claro, em diversas instituições de ensino. No total, 451 questionários foram aplicados, sendo 60 na cidade de Rio Claro e o restante na cidade de São Carlos. Os resultados da pesquisa de campo foram analisados através de métodos de análise estatística descritiva e correlacional, produzindo os seguintes estudos: resultados dos questionários; classificação dos participantes em tipos de ciclistas; definição de uma escala de aceitabilidade ao uso da bicicleta e a classificação dos participantes em grupos, de acordo com esta escala. O Modelo de Nível de Serviço para Bicicletas foi calibrado utilizando-se a variável FLUXO, definida como o volume de veículos motorizados dividido pela largura efetiva da via, e as medidas de nível de serviço provenientes da avaliação realizada pelos participantes da pesquisa. O modelo foi validado através da metodologia da validação cruzada. O desenvolvimento do modelo resultou em um gráfico que pode ser utilizado para determinar a probabilidade da percepção de nível de serviço para valores de fluxo encontrados nas vias. Considera-se que a pesquisa atingiu o seu objetivo principal, fornecendo um Modelo de Nível de Serviço para Bicicletas que pode ser utilizado em cidades brasileiras de porte médio.