An alternative bivariate zero-inflated negative binomial regression model using a copula

We propose an alternative bivariate zero-inflated negative binomial (BZINB) regression model based on a copula. The empirical result shows that the proposed model performs better than the existing BZINB models in terms of the maximum log-likelihood and the AIC.     

A quantitative perspective of Porter's industry forces framework for investment analysis

Porter's industry forces framework is an important tool for external analysis of firms, but its qualitative nature presents numerous limitations to be used in investment analysis. This study introduces a quantitative perspective of the framework using financial information proxies. This allows investors to gauge the external factors quantitatively and to gain enhanced framework usability. In order to test its validity, the correlation movements of our quantitative perspective have been analysed. For demonstration of enhanced usability, our quantitative perspective, alongside machine learning models, was used to predict business performances. The empirical results indicate that our quantitative perspective of the framework corroborates with its original definition and that it exhibits enhanced usability than the original framework.     

The scope of “marketing” research in the nonprofit sector: Lessons from the last 20 years literature

Over the last several decades, the field of nonprofit marketing has produced a growing number of publications; however, little attention has been paid to examine what research topics have been studied by nonprofit scholars from the marketing perspectives. This knowledge production research contributes to the literature by reviewing trends in research themes and methodologies over the last 20 years among the articles for which authors use the terminology “marketing.” Employing a thematic review using text network analysis, and an in-depth methodology review, this study finds that nonprofit marketing studies have been shifting to become more subdivided and diversified in terms of research themes and methodologies. However, we also find that there is still room for further development, which we provided recommendations based on the findings. With its findings, this paper provides critical guidance for future studies.     

Gender Discrimination and Worker Selectivity: A Comparison of the Self-employed and Wage Earners

This study compares the size and nature of the gender earnings differentials for the self-employed and wage earners in Korea, taking into account the workers’ self-selection of each employment type. The two-stage estimates of the earnings equation, corrected for worker selectivity, are used to decompose the gender earnings differentials into productivity-related and discriminatory factors. Our results suggest that the size of the gender earnings gap is larger in the wage sector than in the self-employment sector, but not by large margin, and so is the discrimination effect when not controlled for worker selectivity. With worker selectivity controlled, the discrimination effect is greatly intensified in the wage sector, while it becomes not significant in the self-employment sector. These findings imply that the observed gender earnings gap in the wage sector is largely ascribed to discrimination against women, while the gender earnings gap in the self-employment sector is mostly due to productivity difference that, in part, is caused by worker selectivity.     

Making Sense of One Dollar CEO Salaries

We examine the determinants and outcomes of Chief Executive Officers (CEOs) accepting a $1 salary, a compensation practice that occurs relatively frequently in high‐profile firms and is debated by regulators, investors, and the media. Using a hand‐collected sample of 93 CEOs from 91 firms between 1993 and 2011, we examine the triggers preceding the $1 salary decision, the factors associated with the decision, subsequent stock returns, and the outcomes for the CEOs. Our evidence is consistent with two explanations for the phenomenon: (i) it is a gesture of sacrifice by CEOs of firms in crisis, and (ii) it is a signal of better future performance by CEOs of growing firms. Our analyses highlight the two different circumstances and shed light on an interesting debate that has thus far been supported only by anecdotal evidence.     

Does health insurance decrease health expenditure risk in developing countries? The case of China

This article studies the impact of health insurance on individual out‐of‐pocket health expenditures in China. Using China Health and Nutrition Survey data between 1991 and 2006, we apply two‐part and sample selection models to address issues caused by censored data and selection on unobservables. We find that, although the probability of accessing health care increases with the availability of health insurance, the level of out‐of‐pocket health expenditure decreases. Our results from a selection model with instrumental variables suggest that having health insurance reduces the expected out‐of‐pocket health expenditure of an individual by 29.42% unconditionally. Meanwhile, conditional on being subjected to positive health expenditure, health insurance helps reduce out‐of‐pocket spending by 44.38%. This beneficial effect of health insurance weakens over time, which may be attributable to increases in the coinsurance rates of health insurances in China.     

Some Reflections on U.S. Treaty Commitments

Abstract

The world oil price has risen significantly since the late 1990s and reached a record high in 2008. The recent oil price hike raises concerns regarding the possible negative effects of the rising oil price on the economy as in the 1970s. We investigate the effects of the oil price hike on the Korean economy using a Bayesian dynamic stochastic general equilibrium (DGSE) model. We explicitly model the small open economy nature of the Korean economy and its oil usage and estimate the constructed model within a unified Bayesian framework. We also examine possible changes in the effects of world oil shocks on the Korean economy using counterfactual simulations. We find the adverse effects of world oil shocks as well as their importance in Korean business cycles have diminished due to reductions in the relative usage of crude oil in the economy, while world oil shocks themselves have changed relatively little over time.     

The Rising Supply of College Graduates and Declining Returns for Young Cohort: The Case of Korea

Abstract

This study analysed the effect of an increase in the supply of youth college graduates, in terms of the return on education. The rate of return on education in Korea substantially dropped from 1983 to 1994. Since then, however, the declining trend of the rate of return on education stopped and turned upward. The rate of return has declined especially for college graduates, and such a decline has been most prominent for young cohorts, among college graduates, since 1987. The observed trend of the rate of return appears to be related to the sharp increase of labour supply of college graduates since the mid 1980s.

The elasticity of substitution between education levels and age groups was estimated in this study, using a generalized demand-supply model. The effects of relative supply of college graduates (as a whole and by age) on the relative wages of college graduates by age were analysed under the assumption of constant skill-biased technological change. As it turned out, the relative college graduates’ labour supply of each age group had large bearings upon relative wages of each corresponding group, while the relative labour supply of all college graduates did not. It implies that labour is an imperfect substitute, not only between education levels but also between age groups.

Thus, as youth college graduates’ supply increases, there needs to be a corresponding demand increase for them, to avoid the drop in the wage or employment level for them. Therefore, to tackle with the issues of youth labour market, such as youth unemployment, separate policies targeting the youth group are called for.