Product Introduction Strategies under Sequential Innovation for Durable Goods with Network Effects

When network effects are important and technology is rapidly improved, this study explores the relative optimality of five product introduction strategies of a durable goods manufacturer: (1) replacement, (2) skipping, (3) a delayed line, (4) shelving, and (5) line‐extension. Using a two‐period analytical model, we show how the type of compatibility—either full or backward compatibility—and the magnitude of the network effect influence the manufacturer's preference for the above strategies. Our analysis reveals that only the strategies (1)–(3) above can be optimal; and the optimal strategy varies with network strength. Further, the type of compatibility can dramatically change the profitability under each optimal strategy; for instance, while backward compatibility can increase the profitability of replacement under certain conditions, it always reduces the profitability of a delayed line. We also illustrate that if compatibility were a choice, although backward compatibility may be observed widely in practice, the parametric region for its optimality is relatively more restricted than that of full compatibility.     

Public Perceptions About Sex Offenders and Community Protection Policies

Sex offenders and sex crimes provoke a great deal of anxiety in our society, and over the past decade, lawmakers have passed a variety of social policies designed to protect the public from sexual victimization. The purpose of this study was to examine public perceptions about sex offenders and community protection policies. Data were obtained from a sample of 193 residents in Melbourne, Florida. It was hypothesized that the public holds some inaccurate beliefs about sex offenders, and that there is strong public support for community protection policies. It was found that community members believe that sex offenders have very high recidivism rates, view sex offenders as a homogeneous group with regard to risk, and are skeptical about the benefits of sex offender treatment. The hypothesis that public perceptions contradict empirical research was supported. Community members were overwhelmingly in favor of public disclosure of information about registered sex offenders, although they did not express as much support for residence restrictions. Implications for public policy, and for the media's role in shaping public perceptions, are discussed.     

Relations Between Alphabetized Name Order and Nomination Counts in Peer Nomination Measures

Peer nominations, a central method for measuring peer relationships in developmental research, typically involve asking children or adolescents to choose peers who fit various criteria from an alphabetized roster of classmates or grade‐mates. Although such measures have been used for decades, very little research has investigated the effects of alphabetical name order on the number of nominations received by peers. This study collected peer nominations for 20 items among 607 eighth grade participants in two schools. Regression analyses showed that earlier name order significantly predicted higher nomination counts for eight of the items, and explained over 5 percent of the variance in four affective variables (friendship, acceptance, acquaintanceship, and received liking). Across variables, name order effects were negatively correlated with internal reliability of nominations, implying that order effects may be related to the consensus of the peer group. Name order also had a minimal effect on inter‐correlations among a subset of variables. Implications and concrete recommendations for controlling and reducing name order effects in future research are discussed.     

Determinants of Social Expenditure in Sri Lanka

The study examines the determinants of social expenditure in Sri Lanka for the period 1970–2010. The data are from a new data set assembled by the authors. The social spending data are collected from the Central Bank of Sri Lanka on education, health, and also on welfare spending. The study explains the determinants of social spending considering the demand‐side and the supply‐side driving forces and finds that inequality issues have been a major concern of social policy in Sri Lanka. Similarly, this study implies the influence of political behavior to satisfy voters as explained by the fiscal illusion theory. The globalization is not significant for social expenditure as commonly assumed in developed countries. Even the consequences of the self‐interested behavior of bureaucrats are not evident in the Sri Lankan welfare sector.     

Diesel Engine Exhaust and Lung Cancer Mortality: Time‐Related Factors in Exposure and Risk

To develop a quantitative exposure‐response relationship between concentrations and durations of inhaled diesel engine exhaust (DEE) and increases in lung cancer risks, we examined the role of temporal factors in modifying the estimated effects of exposure to DEE on lung cancer mortality and characterized risk by mine type in the Diesel Exhaust in Miners Study (DEMS) cohort, which followed 12,315 workers through December 1997. We analyzed the data using parametric functions based on concepts of multistage carcinogenesis to directly estimate the hazard functions associated with estimated exposure to a surrogate marker of DEE, respirable elemental carbon (REC). The REC‐associated risk of lung cancer mortality in DEMS is driven by increased risk in only one of four mine types (limestone), with statistically significant heterogeneity by mine type and no significant exposure‐response relationship after removal of the limestone mine workers. Temporal factors, such as duration of exposure, play an important role in determining the risk of lung cancer mortality following exposure to REC, and the relative risk declines after exposure to REC stops. There is evidence of effect modification of risk by attained age. The modifying impact of temporal factors and effect modification by age should be addressed in any quantitative risk assessment (QRA) of DEE. Until there is a better understanding of why the risk appears to be confined to a single mine type, data from DEMS cannot reliably be used for QRA.     

Happily Religious: The Surprising Sources of Happiness Among Lesbian,Gay, Bisexual,and Transgender Adults

This article analyzes the impact of religion on reported levels of subjective well‐being (general happiness) among lesbian, gay, bisexual, and transgender (LGBT) adults. Although previous studies find religious affiliation to be a significant predictor of subjective well‐being among the general population in the United States, limited quantitative research investigates general happiness among sexual and gender minorities. This study augments the existing literature by using a national survey of LGBT adults conducted by the Pew Research Center in 2013. The results show that religious affiliation is a significant predictor of LGBT individuals’ happiness. LGBT individuals who identify as Catholic, agnostic or atheist, or with no particular religious affiliation report lower levels of happiness compared to mainline Protestants. Surprisingly, no significant differences are found between mainline Protestants (whose church doctrine often accepts same‐sex relations) and evangelical Protestants (whose church doctrine often condemns same‐sex relations). In addition, income is the only control variable that affects general happiness. Our analysis reveals interesting differences in the determinants of subjective well‐being between the LGBT and general population.     

Dose‐Response Models Incorporating Aerosol Size Dependency for Francisella tularensis

The effect of bioaerosol size was incorporated into predictive dose‐response models for the effects of inhaled aerosols of Francisella tularensis (the causative agent of tularemia) on rhesus monkeys and guinea pigs with bioaerosol diameters ranging between 1.0 and 24 μm. Aerosol‐size‐dependent models were formulated as modification of the exponential and β‐Poisson dose‐response models and model parameters were estimated using maximum likelihood methods and multiple data sets of quantal dose‐response data for which aerosol sizes of inhaled doses were known. Analysis of F. tularensis dose‐response data was best fit by an exponential dose‐response model with a power function including the particle diameter size substituting for the rate parameter k scaling the applied dose. There were differences in the pathogen's aerosol‐size‐dependence equation and models that better represent the observed dose‐response results than the estimate derived from applying the model developed by the International Commission on Radiological Protection (ICRP, 1994) that relies on differential regional lung deposition for human particle exposure.