Murder, Extramarital Affairs, and the Issue of Probative Value

A paper previously published in Law and Human Behavior by D. Davis and W. C. Follette (2002) argued that certain "profiling" characteristics commonly admitted into court have little or no probative value. They argued that this is especially likely to be true when the characteristic used as evidence (e.g., having an extramarital affair) is rather common in the population whereas the act in question (e.g., a man murdering his wife) is rare. Their analysis has prompted a strong response by Friedman and Park and by Kaye and Koehler with a rejoinder by Davis and Follette (all three follow this paper in this issue of Law and Human Behavior). This paper describes some of the nature of this controversy.     

Polydrug fatality involving metaxalone

A 29-year old female with a history of depression was found dead in a hotel room. The death scene investigation found empty pill bottles and an empty liter bottle of wine. Metaxalone, a centrally acting muscle relaxant, along with citalopram, ethanol, and chlorpheniramine were identified in the postmortem samples and quantitated by gas chromatography-mass spectrometry. The concentration of metaxalone in femoral vein blood was 39 mg/L. The heart blood concentration was 54 mg/L. Femoral vein blood concentrations of citalopram and chlorpheniramine were 0.77 mg/L and 0.04 mg/L, respectively. Ethanol levels were 0.13 g/dL in vitreous and 0.08 g/dL in heart blood. Other tissue samples were also analyzed. The authors consider the metaxalone concentrations toxic and potentially fatal. The citalopram concentrations were lower than those reported in fatal cases for this drug alone. Death was ascribed to polydrug abuse/overdose with metaxalone a major contributor. This represents the first reported case to our knowledge in which a metaxalone overdose significantly contributed to death.     

The poor in Singapore: issues and options

This article examines the changing patterns of poverty in Singapore. As Singapore's population ages, the poor increasingly includes the elderly. It appears that ascribed factors, such as gender and race, have significant influence on financial security at old age. As the population ages, the adequacy of existing anti-poverty policy is challenged.     

Logistic Regression in Rare Events Data

We study rare events data, binary dependent variables with dozensto thousands of times fewer ones (events, such as wars, vetoes,cases of political activism, or epidemiological infections)than zeros ("nonevents"). In many literatures, these variableshave proven difficult to explain and predict, a problem thatseems to have at least two sources. First, popular statisticalprocedures, such as logistic regression, can sharply underestimatethe probability of rare events. We recommend corrections thatoutperform existing methods and change the estimates of absoluteand relative risks by as much as some estimated effects reportedin the literature. Second, commonly used data collection strategiesare grossly inefficient for rare events data. The fear of collectingdata with too few events has led to data collections with hugenumbers of observations but relatively few, and poorly measured,explanatory variables, such as in international conflict datawith more than a quarter-million dyads, only a few of whichare at war. As it turns out, more efficient sampling designsexist for making valid inferences, such as sampling all availableevents (e.g., wars) and a tiny fraction of nonevents (peace).This enables scholars to save as much as 99% of their (nonfixed)data collection costs or to collect much more meaningful explanatoryvariables. We provide methods that link these two results, enablingboth types of corrections to work simultaneously, and softwarethat implements the methods developed.     

Mixed-Sex Settings and the Perception of Competence

This study examines the association of self-perceptions with sixth to eighth graders' exposure to mixed-sex and dating contexts. It contrasts two hypotheses: the stress hypothesis, which suggests that the transition to romantic relationships will be associated with declines in self-esteem, especially for girls, and the leisure hypothesis, which suggests that movement into a desired role in an emotionally positive social context will be associated with positive emotions and higher self-esteem. Results indicate that adolescents experience mixed-sex settings positively, and that comfort with the other sex (for girls) and more time spent with the other sex (for boys) are predictive of more positive self-perceptions. Activity diary data suggest that these differences are due to differences in the emotional climate of same- and mixed-sex settings, rather than to the activities adolescents engage in with same- and mixed-sex groups. Dating boys who are less interested in dating experience lower self-esteem. Results are discussed in light of the transitional nature of mixed-sex relationships in early adolescence and the preparatory role played by same-sex friendships.