The two-sample t test versus satterthwaite's approximate f test

A comparison between the two-sample t test and Satterthwaite's approximate F test is made, assuming the choice between these two tests is based on a preliminary test on the variances. Exact formulas for the sizes and powers of the tests are derived. Sizes and powers are then calculated and compared for several situations.     

On multiple constraint skewed models

The Azzalini [A. Azzalini, A class of distributions which includes the normal ones, Scandi. J. Statist. 12 (1985), pp. 171–178.] skew normal model can be viewed as one involving normal components subject to a single linear constraint. As a natural extension of this model, we discuss skewed models involving multiple linear and nonlinear constraints and possibly non-normal components. Particular attention is devoted to a distribution called the extended two-piece normal (ETN) distribution. This model is a two-constraint extension of the two-piece normal model introduced by Kim [H.J. Kim, On a class of two-piece skew normal distributions, Statistics 39(6) (2005), pp. 537–553.]. Likelihood inference for the ETN distribution is developed and illustrated using two data sets.     

The Construction of Fear

The paper derives applications of an observation about how fears are constructed by people in their daily lives in order to expand upon developments and critiques in constructionist analyses of scares in the news media.     

Peace and Conflict Resolution Organizations in Three Protracted Conflicts: Structures,Resources and Ideology

Guided by organizational and social movement theories, this study compares the structures, resource bases, ideologies, and strategies of nongovernmental organizations engaged in peace and conflict resolution (P/CROs) in three regions with extended violent conflicts: Northern Ireland, South Africa, and Israel/Palestine. Qualitative content analysis techniques are used to analyze 27 detailed case reports. We analyze the funding patterns and structural attributes of the P/CROs in our sample, with particular attention to how they obtain fiscal resources and membership in spite of the risks they may experience. We then explore the degree of formalization among P/CROs over time and, finally, we examine the ideological frames that P/CROs use and how these frames relate to their tactics. Throughout the analysis we pay attention to how the political context of each region influences P/CRO behavior.     

Social intelligence as moderator in the relation between narcissism and aggression in at-risk adolescents

This study examined the moderating role of social intelligence (SI) in the associations of grandiose and vulnerable narcissism (VN) with peer-reported overt and relational aggression (RA). The sample consisted of 286 adolescents aged 15 to 19 recruited from a residential program for youth who have dropped out of school. Results showed that whereas grandiose narcissism (GN) was related to both forms of aggression, VN was related to neither overt nor RA. However, SI moderated the relation between VN and both forms of aggression such that SI works as either a risk or protective factor for adolescents with higher levels of narcissism depending on the subdimensions of SI and aggression. The findings indicate that SI may play a role in how adolescent peers perceive the behavior of relatively narcissistic individuals.     

On the Exact and Near-Exact Distributions of the Product of Generalized Gamma Random Variables and the Generalized Variance

In this article, the authors first obtain the exact distribution of the logarithm of the product of independent generalized Gamma r.v.’s (random variables) in the form of a Generalized Integer Gamma distribution of infinite depth, where all the rate and shape parameters are well identified. Then, by a routine transformation, simple and manageable expressions for the exact distribution of the product of independent generalized Gamma r.v.’s are derived. The method used also enables us to obtain quite easily very accurate, manageable and simple near-exact distributions in the form of Generalized Near-Integer Gamma distributions. Numerical studies are carried out to assess the precision of different approximations to the exact distribution and they show the high accuracy of the approximations provided by the near-exact distributions. As particular cases of the exact distributions obtained we have the distribution of the product of independent Gamma, Weibull, Frechet, Maxwell-Boltzman, Half-Normal, Rayleigh, and Exponential distributions, as well as the exact distribution of the generalized variance, the exact distribution of discriminants or Vandermonde determinants and the exact distribution of any linear combination of generalized Gumbel distributions, as well as yet the distribution of the product of any power of the absolute value of independent Normal r.v.’s.     

The Proximate Determinants of Educational Homogamy: The Effects of First Marriage,Marital Dissolution,Remarriage, and Educational Upgrading

This paper adapts the population balancing equation to develop a framework for studying the proximate determinants of educational homogamy. Using data from the National Longitudinal Survey of Youth on a cohort of women born between 1957 and 1964, we decompose the odds of homogamy in prevailing marriages into four proximate determinants: (1) first marriages, (2) first and later marital dissolutions, (3) remarriages, and (4) educational attainment after marriage. The odds of homogamy among new first marriages are lower than among prevailing marriages, but not because of selective marital dissolution, remarriage, and educational attainment after marriage, as has been speculated. Prevailing marriages are more likely to be educationally homogamous than new first marriages because of the accumulation of homogamous first marriages in the stock of marriages. First marriages overwhelmingly account for the odds of homogamy in prevailing marriages in this cohort. Marital dissolutions, remarriages, and educational upgrades after marriage have relatively small and offsetting effects. Our results suggest that, despite the high prevalence of divorce, remarriage, and continued schooling after marriage in the United States, the key to understanding trends in educational homogamy lies primarily in variation in assortative mating into first marriage.     

Listening to children imagining gender: observing the inflation of an idea

Using three of the clinical articles in this special issue of the Journal of Homosexuality as examples, the author attempts to show how their views of gender may influence clinicians' conceptualizations and treatment choices in response to children diagnosed with gender identity disorder (GID), or gender dysphoria. In particular the author argues that the belief that gender is a psychophysiological entity that is organismic and transhistorical, that is, the view known lately as essentialism, promotes more invasive interventions (e.g., endocrinological and surgical) and mistakenly deemphasizes psychological therapies as a clinical response to the suffering of trans children. He tries to show that the drawbacks of essentialism and its correlated treatment approaches are twofold, that a) they promote treatments with insufficient attention to our limited knowledge regarding their safety and efficacy, and b) they advance a reified differentiation of the genders that is politically problematic. The author suggests that a better response to trans children would be one that emphasizes the child's broadly subjective role in his or her construction of transgressive, gender-related psychological and interpersonal phenomena (both painful and not), thus, offering a deeper validation for trans children's challenges to our gender system.     

Bivariate deconvolution with SIMEX: an application to mapping Alaska earthquake density

Constructing spatial density maps of seismic events, such as earthquake hypocentres, is complicated by the fact that events are not located precisely. In this paper, we present a method for estimating density maps from event locations that are measured with error. The estimator is based on the simulation–extrapolation method of estimation and is appropriate for location errors that are either homoscedastic or heteroscedastic. A simulation study shows that the estimator outperforms the standard estimator of density that ignores location errors in the data, even when location errors are spatially dependent. We apply our method to construct an estimated density map of earthquake hypocenters using data from the Alaska earthquake catalogue.