Wavelet-Based Density Estimation in a Heteroscedastic Convolution Model

We consider a heteroscedastic convolution density model under the “ordinary smooth assumption.” We introduce a new adaptive wavelet estimator based on term-by-term hard thresholding rule. Its asymptotic properties are explored via the minimax approach under the mean integrated squared error over Besov balls. We prove that our estimator attains near optimal rates of convergence (lower bounds are determined). Simulation results are reported to support our theoretical findings.     

Skewed Sex Ratios at Birth and Future Marriage Squeeze in China and India, 2005–2100

I examine the potential impact of the anticipated future marriage squeeze on nuptiality patterns in China and India during the twenty-first century. I use population projections from 2005 to 2100 based on three different scenarios for the sex ratio at birth (SRB). To counteract the limitations of cross-sectional methods commonly used to assess the severity of marriage squeezes, I use a two-sex cohort-based procedure to simulate marriage patterns over the twenty-first century based on the female dominance model. I also examine two more-flexible marriage functions to illustrate the potential impact of changes in marriage schedules as a response to the marriage squeeze. Longitudinal indicators of marriage squeeze indicate that the number of prospective grooms in both countries will exceed that of prospective brides by more 50% for three decades in the most favorable scenario. Rates of male bachelorhood will not peak before 2050, and the squeeze conditions will be felt several decades thereafter, even among cohorts unaffected by adverse SRB. If the SRB is allowed to return to normalcy by 2020, the proportion of men unmarried at age 50 is expected to rise to 15% in China by 2055 and to 10% in India by 2065. India suffers from the additional impact of a delayed fertility transition on its age structures.     

FIRM HETEROGENEITY AND THE PATTERN OF R&D COLLABORATIONS

We consider an oligopoly setting in which firms form pairwise collaborative links in research and development with other firms. Each collaboration generates a value that depends on the identity of the firms that collaborate. First, we provide properties satisfied by pairwise equilibrium networks and efficient networks. Second, we use these properties in two types of situation: (1) there are two groups of firms, and the value of a collaboration is higher when firms belong to the same group; (2) some firms have more innovative capabilities than others. These two situations provide clear insights about how firms' heterogeneity affects both equilibrium and efficient networks. We also show that the most valuable collaborative links do not always appear in equilibrium, and a public policy that increases the value of the most valuable links may lead to a loss of social welfare. (JEL C70, L13, L20)     

On a deconvolution problem under competing risks

Bagai and Prakasa Rao [Analysis of survival data with two dependent competing risks. Biometr J. 1992;7:801–814] considered a competing risks model with two dependent risks. The two risks are initially independent but dependence arises because of the additive effect of an independent risk on the two initially independent risks. They showed that the ratio of failure rates are identifiable in the nonparametric set-up. In this paper, we consider it as a measurement error/deconvolution problem and suggest a nonparametric kernel-type estimator for the ratio of two failure rates. The local error properties of the proposed estimator are studied. Simulation studies show the efficacy of the proposed estimator.     

Gender bias in reproductive behaviour in Georgia,Indonesia, and Vietnam: An application of the own-children method

I present a method for estimating indicators of gender bias in reproductive behaviour, using microdata based on the own-children method. The method is first tested on a large sample from India with both birth history and household records. I then apply the method to Georgia, Indonesia, and Vietnam. My estimates demonstrate that the proportion of Georgian couples expressing a preference for sons in their fertility behaviour closely corresponds to the proportion resorting to sex selection at high parities. I show how individual Indonesian provinces provide examples of both son and daughter preference. The method also allows me to date the onset of sex imbalances at birth in Vietnam. The approach based on the own-children method therefore provides a unique tool for estimating the diversity and intensity of gender bias in reproductive behaviour.     

Influence and Complementarity of Follow-on Managerial Innovations within a Public Organization

Public Organization Review - The objective of this research is to explore the relations between different categories of managerial innovations in public organizations. This paper aims to...     

Transformations in the medicalization of sex: HIV prevention between discipline and biopolitics

This article examines transformations in HIV prevention strategies from the 1980s to the present. Drawing on the concepts of medicalization (Conrad, 2007 ), discipline and biopolitics (Foucault, 1976/ 1988 ), and biomedicalization (Clarke, Fishman, Fosket, Mamo, & Shim, 2003 ), it explores the shift from behavioral to biomedical and surgical prevention techniques-a shift symbolic of a more general trend toward the biomedicalization of sexuality. It argues that, although biomedical and surgical approaches (chemoprevention and male circumcision) have certain benefits, their efficacy is limited and uncertain. They do not guarantee individual protection. The aim is no longer the modification of sexual behavior through disciplinary strategies aimed at the development of subjective and sexual awareness, but the modification of health behavior as a positive response to biomedical recommendations. Through the use of preventative or curative drugs, the same type of sexual awareness is seen as no longer required.     

A cloud-based spatial-temporal inventory for sustainable urban soil management

Spatial and temporal databases that integrate urban tree inventories and soil quality information are needed for modern-day sustainable urban forest management. The objective of this study was to demonstrate the usefulness of low-cost and widely-available technology, such as global positioning system (GPS)–enabled cameras to photo-document sites and cloud-based products and services (Google Picasa and Fusion Tables), to aid in developing sustainable street tree management programs. Google Fusion Tables provide a cloud platform to store, share and map urban tree and soil data over time using internet connected computers, tablets or mobile devices. Although indicators of urban soil quality and best methods to assess it are not yet standardized, we demonstrate here promising indicators that are both useful and easy to incorporate into spatial and temporal databases of trees managed in urban environments. By utilizing technology, we demonstrate that site-specific urban soil quality indicators can be used together with readily-available soil rating systems specific to different plant types as a means to better evaluate and manage conditions for optimal street tree growth and health.