A semi-parametric Bayesian extreme value model using a Dirichlet process mixture of gamma densities

In this paper, we propose a model with a Dirichlet process mixture of gamma densities in the bulk part below threshold and a generalized Pareto density in the tail for extreme value estimation. The proposed model is simple and flexible for posterior density estimation and posterior inference for high quantiles. The model works well even for small sample sizes and in the absence of prior information. We evaluate the performance of the proposed model through a simulation study. Finally, the proposed model is applied to a real environmental data.     

Agency in Fertility Decisions in Western Europe During the Demographic Transition: A Comparative Perspective

We use a set of linked reproductive histories taken from Sweden, the Netherlands, and Spain for the period 1871–1960 to address key issues regarding how reproductive change was linked specifically to mortality and survivorship and more generally to individual agency. Using event-history analysis, this study investigates how the propensity to have additional children was influenced by the number of surviving offspring when reproductive decisions were made. The results suggest that couples were continuously regulating their fertility to achieve reproductive goals. Families experiencing child fatalities show significant increases in the hazard of additional births. In addition, the sex composition of the surviving sibset also appears to have influenced reproductive decisions in a significant but changing way. The findings offer strong proof of active decision-making during the demographic transition and provide an important contribution to the literature on the role of mortality for reproductive change.     

DO WOMEN PAY MORE FOR CREDIT? EVIDENCE FROM ITALY

By using a unique and large data set on loan contracts between banks and microfirms, we find robust evidence that women in Italy pay more for credit than men, although we do not find any evidence that women borrowers are riskier than men. The male/female differential remains even after controlling for a large number of characteristics of the type of business, the borrower, and the structure of the credit market. The result is not driven by lack of credit history, nor by women using a different type of bank than men, since the same bank charges different rates to male and female borrowers.     

Exploiting the balanced scorecard in the Operations Department: the Ducati Motor Holding case

The literature has widely discussed how to measure manufacturing performance. However, even though several indicators have been proposed, manufacturing reporting systems still suffer from a number of problems, which according to recent contributions, can be solved through the adoption of integrated performance measurement systems (PMSs). This article aims at understanding whether such integrated PMSs–namely the balanced scorecard–can actually solve the problems, which usually affect the reporting system of the Operations Department. The article presents a case-study developed in Ducati Motor Holding and then outlines the main conclusions and managerial implications. The empirical analysis demonstrates that the key benefits brought about by the balanced scorecard concern a higher responsiveness of the decision-making process and more intense cooperation among all units related to operations management (namely, manufacturing, logistics, quality management, procurement, maintenance).     

Persistent marriage regimes in changing times

Marriage among women in Latin America occurs early in life and is nearly universal in spite of the social and economic changes and instability in the region. We use demographic measures to illustrate the precociousness, persistence, and universality of marriage during the past 50 years. We argue that marriage is central to social life because families serve as an important cultural institution for countering the vicissitudes of the economy. Women's roles within families and households are key, as has been illustrated by the growth of literature on household survival strategies during the 1980s and 1990s, when the region experienced widespread economic crisis and restructuring.     

Hispanic Ethnicity,Gender, and the Change in the LEP‐Earnings Penalty in the United States During the 1990s*

Objective. Although studies suggest that the earnings of limited‐English‐proficient (LEP) Hispanic men have recently improved relative to the English fluent, it remains unclear as to whether specific Hispanic groups experienced similar improvements. Methods. Using 1990 and 2000 U.S. Census data, this study employs regression, wage decomposition, and quantile regression analyses to examine how gender and Hispanic ethnicity relate to the LEP‐earnings penalty. Results. The LEP‐earnings penalty fell significantly for Mexican‐American men between 1990 and 2000. However, additional results suggest that this penalty increased for Cuban‐American men and women (and, to a lesser extent, for Mexican‐American women). Conclusions. Expanding trade and ethnic networks as well as reduced statistical discrimination have not systematically benefited all LEP Hispanic populations. Therefore, policies designed to enhance English‐language proficiency may yield heterogeneous socioeconomic outcomes along the ethnic, gender, and income class dimensions.     

Using data augmentation to correct for non-ignorable non-response when surrogate data are available: an application to the distribution of hourly pay

Summary.  The paper develops a data augmentation method to estimate the distribution function of a variable, which is partially observed, under a non-ignorable missing data mechanism, and where surrogate data are available. An application to the estimation of hourly pay distributions using UK Labour Force Survey data provides the main motivation. In addition to considering a standard parametric data augmentation method, we consider the use of hot deck imputation methods as part of the data augmentation procedure to improve the robustness of the method. The method proposed is compared with standard methods that are based on an ignorable missing data mechanism, both in a simulation study and in the Labour Force Survey application. The focus is on reducing bias in point estimation, but variance estimation using multiple imputation is also considered briefly.     

It's not who you know,it's how you know them: Who exchanges what with whom?

Reciprocity – doing for others if they have done for you – is a key way people mobilize resources to deal with daily life and seize opportunities. In principle, reciprocity (the Golden Rule) is a universal norm. In practice, it is variable. Personal networks rarely operate as solidarities and as such, people cannot count on all the members of their networks to provide help all the time. Rather, social support comes uncertainly from a variety of ties in networks. This paper uses survey research to understand the variable and contingent nature of reciprocity and inquires about the kinds of resources exchanged between people. We investigate the extent to which interpersonal ties, network characteristics, and people's personal characteristics (e.g., gender) affect the nature of reciprocal relationships. The evidence is extraordinarily clear on one subject – giving support is strongly associated with getting it. Analyses show that getting support from network members is the key to East Yorkers reciprocating – usually in kind but sometimes with other forms of support.     

Playstation and the Power of Unexpected Consequences

It has been suggested that research business strategy is like studying specimens on a wall. By examining successful stories, one can easily identify the strategic factors responsible for such a success, and the greater the success, the more evident those factors are. Timing, strategic positioning, pricing policies, lead-time - everything goes back to the place where it fits best, like a beautiful mosaic. Even competitors' mistakes become more evident, their dull misunderstanding of what the winner was planning as every successful move leads to an even more successful one. The case of Sony PlayStation, the most successful digital games console ever, is no exception and the temptation to explain the rationale behind such an achievement is almost irresistible. As this paper tries to suggest, sometimes ex- post rationalizations hide or avoid part of the truth. Despite PlayStation's success, Sony's strategic choices were, on more than one occasion, driven more by lucky coincidence than by long-range planning. Furthermore, this paper shows how some of the strategic factors behind PlayStation's winning run sprang from decisions taken by lack of alternatives, and that only in the very end was Sony able to understand their full profit potential.