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Modeling travel demand by time of day is gaining increasing attention in travel demand forecasting practice. This is because time of day choice has important implications for mode choice and for quantifying potential modal and time of day shifts in response to traffic congestion and peak period travel demand management strategies. In this context, understanding the causal relationship between time of day (departure time) choice and mode choice behavior would be useful in the development of time of day based travel demand modeling systems both within the four-step modeling paradigm and within newer tour-based and activity-based microsimulation paradigms. This thesis investigates the relationship between departure time choice and mode choice for non-work trips as work trips tend to be constrained with respect to time of day choice. Two alternative causal structures are considered in this thesis: one structure in which departure time choice is determined first and mode choice is subsequently influenced by departure time choice and a second structure in which mode choice is determined first and affects departure time choice. These two causal structures are analyzed in a recursive bivariate probit modeling framework that allows random error covariance. The estimation is performed separately for worker and non-worker samples drawn from the 1999 Southeast Florida Regional Household Travel Survey. For workers, model estimation results show that the causal structure in which departure time choice precedes mode choice performs significantly better. For non-workers, the reverse causal relationship in which mode choice precedes departure time choice is found to be a more suitable joint modeling structure. These two findings can be reasonably explained from a travel behavior perspective and have important implications for advanced travel demand model development and application.

Fertility levels are investigated in the thesis because significant changes have occurred recently in the fertility levels in Turkey. It is necessary to understand the factors related to fertility level declines to determine how people behave with regard to their fertility in Turkey. It is only after understanding people&rsquo / s behavior then it is possible to develop appropriate social and governmental policies. It is possible to evaluate the fertility level declines from different points of view. There are two opposite approaches when evaluating fertility level declines. One of the approaches explaining fertility level declines is the demographic transition theory which uses &ldquo / modernization&rdquo / as the cause of fertility level declines. The &ldquo / other&rdquo / approach is the opposite approach to the modernization theory. Both of these approaches are acceptable approaches from different views. However / this thesis is not written to prove either one of these approaches. The demographic transition or the modernization perspective is used as a tool to determine the variables which cause fertility levels to decline in Turkey. The aim is to provide an understanding of the determinants of fertility levels in Turkey by constituting an econometric model of fertility across the provinces of Turkey by using the panel data estimation. Data for the variables can be found in years from 1980 to 2000. One of the purposes of this thesis in investigating the fertility level declines is to identify which changes occurred in Turkey related to fertility levels between the years 1980-1985, 1985-1990 and 1990-2000. It is found that urbanization gained importance in effecting fertility level declines in the 1985-1990 period as compared to the 1980-1985 period. The other purpose of this thesis is to investigate how different are the fertility levels in the Provinces Prioritized in Development from the &ldquo / other&rdquo / provinces. Although contraception usage is important in effecting fertility levels in the &ldquo / other&rdquo / provinces, this factor is not important in effecting fertility levels in the Provinces Prioritized in Development.

Natural rubber is a major export crop and the sector is an important source of employment in Thailand. Very few rubber studies in the past have examined the demand and supply equations simultaneously and the previously results are dated. The objectives of this study was to estimate the econometric model of demand and supply of natural rubber in Thailand and determine if a relationship exists between the supply of rubber and its determinants. The data contained in the study are secondary time series annual data from 1977-2012. The instrumental variables estimation by two-stage least squares was used to solve and analyze the demand and supply of rubber. Results were statistically significant at 0.01 level, which showed that the U.S. GDP per capita, the estimated price, rainfall and rice price have a significant effect on quantity of rubber production in Thailand with an estimated elasticity of 1.4, 3.3, -3.6 and -2.6, respectively. The implications of the results are assessed through the lens of rubber producers, rubber consumers and agricultural policy makers.

El primer capítulo de la tesis sobre "Estudios Empíricos sobre Capital Humano e Instituciones" presenta estimaciones de retornos a la educación en Alemania y analiza los determinantes de las preferencias educativas. El segundo capítulo utiliza estimaciones de retornos a la experiencia en el país de origen de inmigrantes en Estados Unidos para proporcionar evidencia empírica que el comercio aumenta la acumulación de capital humano en el trabajo, incluso en los países menos desarrollados, resolviendo la ambigüedad teórica si el comercio aumenta o disminuye "learning-by-doing". La acumulación de capital humano en el trabajo es también positivamente asociada con el PIB per capita, un alto nivel de educación y una mayor calidad de políticas e instituciones. El último capítulo analiza el efecto de recursos naturales y asistencia externa sobre la calidad de instituciones, proporcionando evidencia empírica que -contrario a la asistencia externa, la abundancia de mineral y combustible tiende a ser asociada negativamente con la calidad de instituciones si la fragmentación étnica es grande. / The first chapter of the thesis on "Empirical Studies on Human Capital and Institutions" presents estimates of returns to education in Germany and analyses the determinants of educational choices. The second chapter uses estimated returns to home country experience of US immigrants to provide empirical evidence that trade increases on-the-job human capital accumulation even in less developed countries, thereby resolving the theoretical ambiguity whether trade increases or decreases learning-by-doing. Similar to trade, GDP per capita, a high average level of educational attainment and stronger quality of policy and institutions are found to be positively associated with on-the-job human capital accumulation. The last chapter analyses the effect of natural resources and aid on institutions, providing empirical evidence that contrary to aid, mineral and fuel abundance tends to be associated with significantly lower quality of institutions if ethnic fractionalization is large.

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員工分紅制度用以激勵員工，卻對股東權益有『稀釋效果』，其對股東財富之關係如何？本研究將探討員工分紅制度是否能提高公司的市場績效與財務績效，進而彌補因為稀釋效果所造成股東報酬的減少。此外，本研究認為企業在制訂員工分紅政策時，必定會受到公司特性的影響，故本研究亦探討公司特性與員工分紅政策之間是否具有關連性。實證結果發現，員工分紅制度與公司績效之關連性方面，現金紅利與會計績效間呈現正向相互影響，與市場績效呈現負向相互影響，而股票紅利與市場績效間存有負向相互影響，且無法顯著提升會計績效。員工分紅政策與公司特性之關連性方面，公司規模、人力資源重要性、成長機會與員工紅利成現正相關，唯成長機會與現金紅利無顯著相關。 / The employee bonus policy in Taiwan makes manifest contribution to the upgrade of local high-tech firms. Such policy attracts eminent employees while causing direct losses to the equity of stockholders. Is it definitely a good policy? This study investigates if this policy improves firms’ accounting performance and market performance and if there exists an association between the employee bonus policy and firms’ characteristics. The results indicate that there is a positive relationship between the employee bonus and accounting performance, but accounting performance doesn’t have significant positive effect on stock bonus. Negative association between the employee bonus and accounting performance exists, but the negative relationship between cash bonus and market performance is not significant. The firm size, importance of human resource and opportunity of growth all have positive effects on the employee bonus, but opportunity of growth has no significant effect on cash bonus.

This thesis examines how an econometric model, which allows for simultaneity, performs when estimating electricity supply and demand on the Swedish aggregated electricity market, divided into its four price areas. Previous research and theory points to the importance of taking simultaneity into consideration when estimating simultaneous equation models. The purpose of the thesis is to clarify whether a simultaneous equation model is adequate for estimation of the Swedish electricity market. To answer the question, the existence of simultaneity between electricity price and quantity (produced and consumed electricity) is examined. Regression analyses are performed for each price area and the coefficients are estimated with 2SLS, while Hausman tests and F-tests are carried out to unveil potential simultaneity. The results show that the performance of the model of the thesis varies: the coefficients of the price variables in the demand functions are never statistically significant, while the coefficients of the monthly dummy variables in most cases have expected signs and are statistically significant, especially during summer. Regarding the supply side, the results show that net export have the expected positive statistically significant effect on quantity of electricity supplied in price areas 2, 3, and 4, while the signs and significance of the coefficients of the price variables varies. A price increase in area 3 has a statistically significant positive effect on supply in all areas, while the price of area 4 has a statistically significant negative effect on supply in area 3 and 4. A price increase in area 1 leads to a statistically significant positive effect on supply only in area 2, while such a change in the price of area 2 is associated with a statistically significant decrease of the supply in that same area. As to simultaneity between price and quantity demanded, the Hausman tests gives sufficient evidence to conclude that simultaneity exists in all price areas. Similarly, on the supply side the performed F-tests result in clear evidence of existence of simultaneity. / Denna uppsats undersöker hur en ekonometrisk modell som tar hänsyn till simultanitet presterar vid estimering av utbjuden och efterfrågad kvantitet av elektricitet på den svenska aggregerade elmarknaden, uppdelad efter de fyra elområdena. Tidigare forskning och teori visar på betydelsen av att ta simultanitet i beaktning när simultana ekvationsmodeller estimeras. Uppsatsen syftar till att klarlägga om en simultan ekvationsmodell är lämplig för estimering av den svenska elmarknaden. För att få svar på frågan undersöks om det förekommer simultanitet mellan elpris och kvantitet (producerad och konsumerad el). Regressionsanalyser utförs för varje elområde och koefficienterna skattas med hjälp av 2SLS, medan Hausmantest och F-test utförs för att upptäcka eventuell simultanitet. Uppsatsens modell levererar varierande resultat: i efterfrågeekvationerna är prisvariabeln aldrig statistiskt signifikant medan månadsvariablerna i de flesta fall har förväntat tecken och är statistiskt signifikanta, framför allt under sommarhalvåret. För utbudssidan visar resultatet att nettoexport har väntad positiv statistiskt signifikant effekt på utbjuden kvantitet i elområde 2, 3 och 4, medan tecken och signifikans för prisvariablernas koefficienter varierar. En ökning av priset i område 3 leder till en statistiskt signifikant utbudsökning i alla områden, medan priset i område 4 har en statistiskt signifikant negativ effekt på utbudet i område 3 och 4. En prisökning i elområde 1 leder endast till en statistiskt signifikant positiv utbudsökning i område 2, medan en prisökning i elområde 2 i stället endast leder till en statistiskt signifikant utbudsminskning i samma område. Vad gäller simultanitet mellan pris och kvantitet på efterfrågesidan visar Hausmantesten att det finns tillräckligt starka statistiska bevis för att påstå att simultanitet förekommer i alla elområden. Även för utbudssidan resulterar de utförda F-testen i tydliga bevis för förekomst av simultanitet.

We investigate possible usage of Errors-in-Variables estimator (EIV), when esti- mating structural equations models (SEM). Structural equations modelling pro- vides framework for analysing complex relations among set of random variables where for example the response variable in one equation plays role of the predic- tor in another equation. First an overview of SEM and some common covariance based estimators is provided. Special case of linear regression model is investi- gated, showing that the covariance based estimators yield the same results as ordinary least squares. A compact review of EIV models follows, Errors-in-Variables models are re- gression models where not only response but also predictors are assumed to be measured with an error. Main contribution of this paper then lies in defining modifications of the EIV estimator to fit in the SEM framework. General opti- mization problem to estimate the parameters of structural equations model with errors-in-variables si postulated. Several modifications of two stage least squares are also proposed for future research. Equation-wise Errors-in-Variables estimator is proposed to estimate the coeffi- cients of structural equations model. The coefficients of every structural equation are estimated separately using EIV estimator. Some theoretical conditions...