Assessing the performance of variational methods for mixed logistic regression models

We present a variational estimation method for the mixed logistic regression model. The method is based on a lower bound approximation of the logistic function [Jaakkola, J.S. and Jordan, M.I., 2000, Bayesian parameter estimation via variational methods. Statistics & Computing, 10, 25–37.]. Based on the approximation, an EM algorithm can be derived that results in a considerable simplification of the maximization problem in that it does not require the numerical evaluation of integrals over the random effects. We assess the performance of the variational method for the mixed logistic regression model in a simulation study and an empirical data example, and compare it to Laplace's method. The results indicate that the variational method is a viable choice for estimating the fixed effects of the mixed logistic regression model under the condition that the number of outcomes within each cluster is sufficiently high.     

HPV vaccine acceptance among a sample of Southern men who have sex with men: A comparison of younger and older men

Objectives: Do short, online educational messages about the human papillomavirus (HPV) influence younger and older men who have sex with men (MSM) differently? Second, what are the HPV knowledge levels and risk perceptions of Southern MSM living outside of major metropolitan areas? Methods: This study draws on participants who completed an anonymous online survey asking about their knowledge, risk assessment, and vaccine acceptance regarding HPV. Results: Knowledge about HPV was low among the MSM in this study. After reading a one-page information intervention, vaccine acceptability increased by a statistically significant amount among both a Younger and Older cohort but risk perception only increased among the younger respondents. Single men regardless of age cohort reported sharper increases in perceived risk after the intervention, but relationship status did not produce significant differences in vaccine acceptability. Conclusion: Online, brief interventions may be effective means of increasing motivation to vaccinate among Southern MSM.     

A decade of changes: Within-group analysis of LGBTQ individuals' perceptions of their community context and the relevance for social service providers

The previous decade has seen a drastic shift in the social environment for lesbian, gay, bisexual, transgender, and queer (LGBTQ) people. It is not surprising then to find that the perceived “best” and “worst” aspects of life for nonmetropolitan LGBTQ individuals have also changed. We use data from two cohorts of the Rainbow Illinois survey to examine differences between responses in 2000 and 2011. Furthermore, we examine demographic differences in the perception of what is “best” and “worst” among the 2011 cohort. Results suggest that although the general social climate has improved for some, it remains problematic for others. Implications for social service providers are thoroughly discussed.     

Elasticity function of a discrete random variable and its properties

Elasticity (or elasticity function) is a new concept that allows us to characterize the probability distribution of any random variable in the same way as characteristic functions and hazard and reverse hazard functions do. Initially defined for continuous variables, it was necessary to extend the definition of elasticity and study its properties in the case of discrete variables. A first attempt to define discrete elasticity is seen in Veres-Ferrer and Pavía (2014a). This paper develops this definition and makes a comparative study of its properties, relating them to the properties shown by discrete hazard and reverse hazard, as both defined in Chechile (2011). Similar to continuous elasticity, one of the most interesting properties of discrete elasticity focuses on the rate of change that this undergoes throughout its support. This paper centers on the study of the rate of change and develops a set of properties that allows us to carry out a detailed analysis. Finally, it addresses the calculation of the elasticity for the resulting variable obtained from discretizing a continuous random variable, distinguishing whether its domain is in real positives or negatives.     

Scanner Data and the Treatment of Quality Change in Nonrevisable Price Indexes

The recently developed rolling year GEKS procedure makes maximum use of all matches in the data to construct nonrevisable price indexes that are approximately free from chain drift. A potential weakness is that unmatched items are ignored. In this article we use imputation Törnqvist price indexes as inputs into the rolling year GEKS procedure. These indexes account for quality changes by imputing the “missing prices” associated with new and disappearing items. Three imputation methods are discussed. The first method makes explicit imputations using a hedonic regression model which is estimated for each time period. The other two methods make implicit imputations; they are based on time dummy hedonic and time-product dummy regression models and are estimated on bilateral pooled data. We present empirical evidence for New Zealand from scanner data on eight consumer electronics products and find that accounting for quality change can make a substantial difference.     

Estimating the population proportion in modified ranked set sampling methods

In this paper, proportion estimators and associated variance estimators are proposed for a binary variable with a concomitant variable based on modified ranked set sampling methods, which are extreme ranked set sampling (ERSS), median ranked set sampling (MRSS), percentile ranked set sampling (Per-RSS) and L ranked set sampling (LRSS) methods. The Monte Carlo simulation study is performed to compare the performance of the estimators based on bias, mean squared error, and relative efficiency for different levels of correlation coefficient, set and cycle sizes under normal and log-normal distributions. Moreover, the study is supported with real data application.     

Are VAT reforms an effective tool for promoting culture? A quasi-experiment in Spain

Sponsoring culture is a long-term profit-generating investment that public policy makers can achieve by means of Pigouvian subsidy or tax schemes. This paper evaluates the effectiveness of the three VAT reforms implemented between 2012 and 2018 (one tax raise reform and two tax cut reforms) in the cultural sector in Spain. We first provide visual evidence and empirical estimates of the tax shifting and the distribution of the VAT burden between consumers and producers. We then use a regression discontinuity design to assess the causal effects of these VAT reforms on performing acts and cinema consumption (both in the extensive and the intensive margin). Several interesting findings arise from our results. First, we find that producers only passed through 45% of the VAT cut to consumer prices. Second, the effect of the 2017 VAT reduction on performing arts slightly increased the number of households consuming these cultural services, whereas the 2018 tax cut on cinema had no significant effect in the number of moviegoers (extensive margin). Third, the cultural spending per household conditional on participation (intensive margin) increased after the two VAT rate reductions. Finally, we test for asymmetries in pass-through with respect to the 2012 tax raise and we find (i) no evidence of prices responding more strongly to increases than to decreases in VAT, (ii) a symmetric response of the number of households consuming these cultural services, and (iii) an asymmetric response of the average cultural spending conditional on participation.     

Lagging behind in suburbia: Suburban versus urban newcomers’ employment settlement service outcomes in Metro Vancouver,Canada

Suburbanization is reshaping the context of immigrant settlement in Canada. Newcomer immigrants are increasingly settling initially in suburban communities as opposed to traditional receiving neighborhoods in urban centers. However, the quality of settlement services for newcomers to suburban neighborhoods has lagged behind, creating a mismatch between newcomer settlement patterns and service provision. As settlement patterns are recognized as significant determinants of employment success for newcomers and employment achievement is a key theme of integration, this study compares suburban and urban newcomers’ satisfaction with employment settlement services, associated financial experiences and coping mechanisms. Drawing upon qualitative interviews with 43 newcomer immigrants in Vancouver and three surrounding suburbs, we argue that suburban newcomers experience more difficulties with employment services from settlement service agencies than do urban newcomers. Subsequent unemployment may contribute to suburban settlers experiencing greater difficulty paying their monthly bills than do urban immigrants.