Econometrics: A Bird’s Eye View

As a unified discipline, econometrics is still relatively young and has been transforming and expanding very rapidly over the past few decades. Major advances have taken place in the analysis of cross sectional data by means of semi-parametric and non-parametric techniques. Heterogeneity of economic relations across individuals, firms and industries is increasingly acknowledged and attempts have been made to take them into account either by integrating out their effects or by modeling the sources of heterogeneity when suitable panel data exists. The counterfactual considerations that underlie policy analysis and treatment evaluation have been given a more satisfactory foundation. New time series econometric techniques have been developed and employed extensively in the areas of macroeconometrics and finance. Non-linear econometric techniques are used increasingly in the analysis of cross section and time series observations. Applications of Bayesian techniques to econometric problems have been given new impetus largely thanks to advances in computer power and computational techniques. The use of Bayesian techniques have in turn provided the investigators with a unifying framework where the tasks of forecasting, decision making, model evaluation and learning can be considered as parts of the same interactive and iterative process; thus paving the way for establishing the foundation of “real time econometrics”. This paper attempts to provide an overview of some of these developments.history of econometrics, microeconometrics, macroeconometrics, Bayesian econometrics, nonparametric and semi-parametric analysis

Econometrics: A bird's eye view

As a unified discipline, econometrics is still relatively young and has been transforming and expanding very rapidly over the past few decades. Major advances have taken place in the analysis of cross sectional data by means of semi-parametric and non-parametric techniques. Heterogeneity of economic relations across individuals, firms and industries is increasingly acknowledge and attempts have been made to take them into account either by integrating out their effects or by modeling the sources of heterogeneity when suitable panel data exists. The counterfactual considerations that underlie policy analysis and treatment evaluation have been given a more satisfactory foundation. New time series econometric techniques have been developed and employed extensively in the areas of macroeconometrics and finance. Non-linear econometric techniques are used increasingly in the analysis of cross section and time series observations. Applications of Bayesian techniques to econometric problems have been given new impetus largely thanks to advances in computer power and computational techniques. The use of Bayesian techniques have in turn provided the investigators with a unifying framework where the tasks and forecasting, decision making, model evaluation and learning can be considered as parts of the same interactive and iterative process; thus paving the way for establishing the foundation of the "real time econometrics". This paper attempts to provide an overview of some of these developments

Essays on poverty issues: microeconomic evidence from african countries

Using household level panel data, the thesis provides comprehensive empirical evidence on poverty issues. The thesis constructs spatial and inter-temporal utility consistent poverty lines for Uganda, which are used as inputs to study the sources of poverty, distinguish chronic poverty from transitory poverty and the mechanisms affecting poverty persistence. Based on these poverty lines which are consistent across space and time, the poverty headcount in Uganda increases by about 9% as one moves from 2005 to 2009. In contrast, the official report suggests a reduction in poverty headcount by about 4.5% which is mainly due to low food and non-food consumer price indexes and low food share. Poverty in Uganda is largely chronic. The highest burden of inter-temporal poverty ascribes to households living in the North. Households with a large number of dependent members contribute to inter-temporal poverty more than their population share. The thesis estimates the dynamic random effect probit models and endogenous switching regression. After controlling for observed and unobserved differences in individual characteristics, the thesis still finds strong evidence of state dependence, which is that past poverty actually increases the risk of future poverty. In the presence of genuine state dependence, short run polices are effective. Since consumption in the household surveys is often measured with error, the thesis applies the mixed latent Markov model to estimate the extent of true mobility into and out of poverty. It finds that measurement error overstates the observed poverty transition probabilities or understates the true poverty persistence. Since the actual poverty persistence rate is at least 61%, the poverty in Uganda is largely permanent, not transitory. Measurement error also understates the impacts of observed individual characteristics on making poverty transition from one state to another. Land size per capita, having mobile phone and TV-radio reduce the probability of transiting into poverty as well as increase the chances of poverty exit. The empirical evidence suggests that policy makers have to target households whose consumption slightly above the poverty line and households who are very poor. Since poverty is state dependence, short run policies are effective to keep individuals not to fall into poverty in the first place because once they are poor, they are less likely to exit poverty. Since poverty is mainly chronic in Uganda, on the other hand, long term intervention through increasing human and physical capital and the returns to these assets is effective to the very poor households. Using employer- employee panel data from Ghana, the thesis also finds that poor women are disproportionately sorting into low paying firms. Even after controlling for gender difference in individuals endowments and sorting effects, firms actually pay different wage premium for comparable female and male. When wage inequality increases among the poor, chronic poverty increases. The result suggests that targeting female dominant firms to increase their productivity helps mitigate the national level chronic poverty. The thesis also identifies the type of firms that pay equal premium for comparable gender attributes

Untangling hotel industry’s inefficiency: An SFA approach applied to a renowned Portuguese hotel chain

The present paper explores the technical efficiency of four hotels from Teixeira Duarte Group - a renowned Portuguese hotel chain. An efficiency ranking is established from these four hotel units located in Portugal using Stochastic Frontier Analysis. This methodology allows to discriminate between measurement error and systematic inefficiencies in the estimation process enabling to investigate the main inefficiency causes. Several suggestions concerning efficiency improvement are undertaken for each hotel studied.info:eu-repo/semantics/publishedVersio

Estudi de la coautoria de publicacions científiques entre UPC i nou universitats dels Estats Units: Brown University, University of Chicago, Northwestern University, Stanford University, Columbia University, Cornell University, Harvard University, Princeton University i Duke University

S'analitza la coautoria de la UPC amb autors vinculats a institucions acadèmiques dels Estats Units, per totes les àrees temàtiques i sense considerar límits cronològics o documentals.Postprint (published version

Post-marketing evaluation of adhd drug treatment in children and young adults

Attention Deficit Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder affecting 3-5% of children. In the UK, three drugs are licensed for its treatment; methylphenidate, dexamfetamine and atomoxetine. There is a lack of evidence on the prescribing of these to UK patients; however the common belief, particularly in the media, is that these drugs are over-prescribed. In addition, ADHD was once considered a condition of childhood alone; however increasing evidence suggests that the condition persists into adulthood in a significant number of patients. Again, there is little data on the use of these medications in older adolescents and young adults. Finally, in recent times, there has been much debate and concern over the safety of these drugs due to a number of spontaneous reports of sudden death in patients taking these medications. In light of these issues, this study had the following objectives; 1) to examine the utilisation of these drugs; 2) to examine prescribing of these medications to older patients; 3) to examine the safety of these medications, in particular the issue of sudden death. This was a pharmacoepidemiological study which mainly utilised data from the General Practice Research Database (GPRD), a computerised database of anonymised patient records from approximately 5% of the UK population. The study showed that 1) prevalence of prescribing of these drugs has increased significantly over the last decade, however the prevalence of prescribing is much lower than prescribing rates reported in other countries; 2) prevalence of prescribing of these drugs decreases dramatically in older patients; 3) no increase in the rate of death or sudden death in patients taking these drugs was detected when compared to mortality rates from the general population

Patterns of health care utilization in Vietnam : analysis of 1997-98 Vietnam Living Standards Survey Data

The author provides an econometric analysis of health care utilization in Vietnam based on individual and household level data from the 1997-98 Vietnam Living Standards Survey. The author focuses on the major features of health care utilization patterns, including the determinants of largely self-prescribed use of pharmaceutical drugs, and the use of government hospitals, commune health centers, and private health facilities. The role of income and health insurance is emphasized. Econometric models are estimated for use probability and frequency of contact for all major categories of care, and for individual and household medical expenditure. Econometric results reveal differential responses to income changes at different levels of income. Commune health centers and self-medication are normal goods at lower income levels but inferior goods at higher income levels. The author discusses the policy implications of these results.Health Economics&Finance,Health Systems Development&Reform,Health Monitoring&Evaluation,Public Health Promotion,Environmental Economics&Policies,Health Systems Development&Reform,Environmental Economics&Policies,Insurance&Risk Mitigation,Health Economics&Finance,Health Monitoring&Evaluation