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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Do mergers of large local governments reduce expenditures? - Evidence from Germany using the synthetic control method

Roesel, Felix 20 October 2017 (has links)
States merge local governments to achieve economies of scale. Little is known to which extent mergers of county-sized local governments reduce expenditures, and influence political outcomes. I use the synthetic control method to identify the effect of mergers of large local governments in Germany (districts) on public expenditures. In 2008, the German state of Saxony reduced the number of districts from 22 to 10. Average district population increased substantially from 113,000 to 290,000 inhabitants. I construct a synthetic counterfactual from states that did not merge districts for years. The results do neither show reductions in total expenditures, nor in expenditures for administration, education, and social care. There seems to be no scale effects in jurisdictions of more than 100,000 inhabitants. By contrast, I find evidence that mergers decreased the number of candidates and voter turnout in district elections while vote shares for populist right-wing parties increased.
32

Dopad kurzového závazku ČNB na český export / The impact of CNB's exchange rate commitment on Czech exports

Teichman, Jiří January 2019 (has links)
The thesis evaluates the effect of Czech National Bank's exchange rate commit- ment on Czech sectoral exports. Thus, we show how unconventional monetary policies could affect the exports. To assess the impact of interventions, we use Synthetic Control Method. The method constructs synthetic Czech exports from data of comparable countries that were not under the policy of inter- est and compares them to observed Czech exports following the interventions. We expect a positive effect of Czech National Bank's commitment on Czech exports, because the interventions resulted in the undervaluation of koruna causing a higher demand for Czech goods abroad. Additionally, the exporters should benefit from reduced uncertainty caused by no exchange rate volatility with the euro area. The results showed a positive impact of interventions only in half of the export sectors. The positive effect of a stable exchange rate is not confirmed, because the effect on the euro area countries in some categories was smaller than for the other countries. The results for total sectoral exports were stable across model specifications and confirmed by analysis of Czech bi- lateral sectoral exports to the largest destinations. The significant contribution of this thesis is application of Synthetic Control Method on total sectoral...
33

Bayesian hierarchical spatial and spatio-temporal modeling and mapping of tuberculosis in Kenya.

Iddrisu, Abdul-Karim. 20 December 2013 (has links)
Global spread of infectious disease threatens the well-being of human, domestic, and wildlife health. A proper understanding of global distribution of these diseases is an important part of disease management and policy making. However, data are subject to complexities by heterogeneity across host classes and space-time epidemic processes [Waller et al., 1997, Hosseini et al., 2006]. The use of frequentist methods in Biostatistics and epidemiology are common and are therefore extensively utilized in answering varied research questions. In this thesis, we proposed the Hierarchical Bayesian approach to study the spatial and the spatio-temporal pattern of tuberculosis in Kenya [Knorr-Held et al., 1998, Knorr-Held, 1999, L opez-Qu lez and Munoz, 2009, Waller et al., 1997, Julian Besag, 1991]. Space and time interaction of risk (ψ[ij]) is an important factor considered in this thesis. The Markov Chain Monte Carlo (MCMC) method via WinBUGS and R packages were used for simulations [Ntzoufras, 2011, Congdon, 2010, David et al., 1995, Gimenez et al., 2009, Brian, 2003], and the Deviance Information Criterion (DIC), proposed by [Spiegelhalter et al., 2002], used for models comparison and selection. Variation in TB risk is observed among Kenya counties and clustering among counties with high TB relative risk (RR). HIV prevalence is identified as the dominant determinant of TB. We found clustering and heterogeneity of risk among high rate counties and the overall TB risk is slightly decreasing from 2002-2009. Interaction of TB relative risk in space and time is found to be increasing among rural counties that share boundaries with urban counties with high TB risk. This is as a result of the ability of models to borrow strength from neighbouring counties, such that near by counties have similar risk. Although the approaches are less than ideal, we hope that our formulations provide a useful stepping stone in the development of spatial and spatio-temporal methodology for the statistical analysis of risk from TB in Kenya. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2013.
34

AN EVALUATION OF THE TRAVELING WAVE ULTRASONIC MOTOR FOR FORCE FEEDBACK APPLICATIONS

Venkatesan, Nishant 01 January 2009 (has links)
The traveling wave ultrasonic motor is considered for use in haptic devices where a certain input-output relation is desired between the applied force and the resulting motion. Historically, DC motors have been the standard choice for this purpose. Owing to its unique characteristics, the ultrasonic motors have been considered an attractive alternative. However, there are some limitations when using the ultrasonic motor for force-feedback applications. In particular, direct torque control is difficult, and the motor can only supply torque in the direction of motion. To accommodate these limitations we developed an indirect control approach. The experimental results demonstrate that the model reference control method was able to approximate a second order spring-damper system.
35

A case-control study of tea/coffee consumption and lung cancer risk.

Fujiwara, Atsuko. Roberts, Robert E., Forman, Michele R. Felknor, Sarah Anne. January 2008 (has links)
Thesis (M.P.H.)--University of Texas Health Science Center at Houston, School of Public Health, 2008. / Source: Masters Abstracts International, Volume: 47-01, page: . Advisers: Robert E. Roberts; Michele Forman. Includes bibliographical references.
36

Estimating crash modification factors for lane-departure countermeasures in Kansas

Galgamuwa, Uditha Nandun January 1900 (has links)
Doctor of Philosophy / Department of Civil Engineering / Sunanda Dissanayake / Lane-departure crashes are the most predominant crash type in Kansas which causes very high number of motor vehicle fatalities. Therefore, the Kansas Department of Transportation (KDOT) has implemented several different types of countermeasures to reduce the number of motor vehicle fatalities associated with lane-departure crashes. This research was conducted to estimate the safety effectiveness of commonly used lane-departure countermeasures in Kansas on all crashes and lane-departure crashes using Crash Modification Factors (CMFs). Paved shoulders, rumble strips, safety edge treatments and median cable barriers were identified as the commonly used lane-departure countermeasures on both tangent and curved road segments while chevrons and post-mounted delineators were identified as the most commonly used lane-departure countermeasures on curved road segments. This research proposes a state-of-art method of estimating CMFs using cross-sectional data for chevrons and post-mounted delineators. Furthermore, another state-of-art method is proposed in this research to estimate CMFs for safety edge treatments using before-and-after data. Considering the difficulties of finding the exact date of implementation of each countermeasure, both cross-sectional and before-and-after studies were employed to estimate the CMFs. Cross-sectional and case-control methods, which are the two major methods in cross-sectional studies were employed to estimate CMFs for paved shoulders, rumble strips, and median cable barriers. The conventional cross-sectional and case-control methods were modified when estimating CMFs for chevrons and post-mounted delineators by incorporating environmental and human behaviors in addition to geometric and traffic-related explanatory variables. The proposed method is novel and has not been used in the previous cross-sectional models available in the literature. Generalized linear regression models assuming negative binomial error structure were used to develop models for cross-sectional method to estimate CMFs while logistic regression models were used to estimate CMFs using case-control method. Results showed that incorporating environmental and human-related variables into cross-sectional models provide better model fit than in conventional cross-sectional models. To validate the developed models for cross-sectional method, mean of the residuals and the Root Mean Square Error (RMSE) were used. For the case-control method, Receiver Operational Characteristic (ROC) was used to evaluate the predictive power of models for a binary outcome using classification tables. However, it was seen that the case-control method is not suitable for estimating CMFs for all crashes since the range of the crash frequency is wide in each road segment. A regression-based method of estimating CMFs using before-and-after data was proposed to estimate CMFs for safety edge treatments. This method allows researchers to identify the safety effectiveness of an individual CMFs on road segments where multiple treatments have been applied at the same time. Since this method uses road geometric and traffic-related characteristics in addition to countermeasure information as the explanatory variables, the model itself would be the Safety Performance Function (SPF). Therefore, developing new SPF is not necessary. Finally, the CMFs were estimated using before-and-after Empirical Bayes method to validate the results from the regression-based method. The results of this study can be used as a decision-making tool when implementing lane-departure countermeasures on similar roadways in Kansas. Even though there are readily available CMFs from the national level studies, having more localized CMFs will be beneficial due to differences in traffic-related and geometric characteristics on different roadways.
37

Three Essays on Housing Markets, Urban Land Use, and the Environment

Ahn, Jae-Wan 29 August 2019 (has links)
No description available.
38

The Economic Effect of Membership in the European Union – The Case of Sweden : Using the Synthetic Control Method and Difference-in-Differences Method

Eklund, Agnes January 2022 (has links)
This thesis aims to examine the economic effect in terms of real GDP at constant 2017 national prices (in mil. 2017 US$) of being a member in the European Union in the case of Sweden. The method used to answer the research question is mainly by the Synthetic Control Method. Difference-in-difference estimations were also conducted as a complement to compare the results between the two methods. Previous literature in the subject has for the most part received results indicating that a membership in the European Union contributes to an increase in certain economic growth aspects for the member countries. The economic theories about common markets points at that a common market can be both advantageous but also disadvantageous depending on the setting. Theories more closely related to the European Union present rather ambiguous answers to certain economic effects of a membership but in some cases, it seems to be possible to assume some positive economic effect from being a European Union-member. The results in this paper seem to be robust in the way that the effect on the real GDP at constant 2017 national prices (in mil. 2017 US$) in Sweden from its membership in the European Union is negative in all estimations that were made. However, none of the results were statistically significant so there is not enough evidence to say that the Swedish real GDP at constant 2017 national prices (in mil. 2017 US$) would have been different to the factual outcome if Sweden did not join the European Union in 1995.
39

Actual Entities: A Control Method for Unmanned Aerial Vehicles

Absetz, Erica 25 April 2013 (has links)
The focus of this thesis is on Actual Entities, a concept created by the philosopher Alfred North Whitehead, and how the concept can be applied to Unmanned Aerial Vehicles as a behavioral control method. Actual Entities are vector based, atomic units that use a method called prehension to observe their environment and react with various actions. When combining multiple Actual Entities a Colony of Prehending Entities is created; when observing their prehensions an intelligent behavior emerges. By applying the characteristics of Actual Entities to Unmanned Aerial Vehicles, specifically in a situation where they are searching for targets, this emergent, intelligent behavior can be seen as they search a designated area and locate specified targets. They will alter their movements based on the prehensions of the environment, surrounding Unmanned Aerial Vehicles, and targets.
40

Estimating the Euro effect with Synthetic Control Method for Eastern Europe / Estimating the Euro effect with Synthetic Control Method for Eastern Europe

Janota, Martin January 2015 (has links)
Estimating the Euro effect with Synthetic Control Method for Eastern Europe Abstract This thesis estimates the effect of Euro adoption on newest Eurozone members using synthetic control method. The effect is estimated on income per capita and GDP growth. Estimates indicate overall indecisive effect for Slovakia and Malta, neutral effect for Estonia and negative effect for Slovenia and Cyprus. The cost of Euro for Cyprus is estimated to be as high as 1/3 of GDP per capita. In some cases the direction of the effect changed before and after the financial crisis. The quality of inference suffers from low number of observations. Methodological assumptions are discussed, concluding that quality of Eastern European time series likely causes substantial bias in the results.

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