Assessing nontraditional couples: validity of the marital satisfaction inventory--revised with gay,lesbian, and cohabiting heterosexual couples

Thirty-one gay male couples and 28 lesbian couples were compared with 36 cohabiting heterosexual couples using the Marital Satisfaction Inventory-Revised (MSI-R), a multidimensional measure of relationship functioning intended for use with both traditional and nontraditional couples. Analyses of scales' internal consistency and factor structure supported the construct validity of this measure with nontraditional couples. Analyses of mean profiles on the MSI-R indicated that cohabiting opposite-gender and same-gender couples were more alike than different, and were more similar to nondistressed samples of married heterosexual couples from the general community than to couples in therapy. Implications of current findings for clinical assessment and intervention are considered, and directions for future research are proposed.     

Conflicting evidence and decisions by agency professionals: an experimental test in the context of merger regulation

Many important regulatory decisions are taken by professionals employing limited and conflicting evidence. We conduct an experiment in a merger regulation setting, identifying the role of different standards of proof, volumes of evidence, cost of error and professional or lay decision making. The experiment was conducted on current practitioners from 11 different jurisdictions, in addition to student subjects. Legal standards of proof significantly affect decisions. There are specific differences because of professional judgment, including in how error costs and volume of evidence are taken into account. We narrow the range of explanations for why professional decision making matters.     

Book Review: Making a Life in Yorkville: Experience and Meaning in the Life-Course Narrative of an Urban Working-Class Man. By Handel,Gerald. Westport,CT: Greenwood Press, 2000. 149 pages,hardback, ISBN: 0-313-31307-5

Qualitative Sociology -     

Generalized model for IGC growth in aluminum alloys

A generalized brick wall model is developed to describe intergranular corrosion in Equi-axed AA7178-T6 and Wingskin AA7178-T6 aluminum alloys. The intergranular corrosion rate is highly related to grain size and shape. High strength aluminum alloys are often elongated and anisotropic, with the fastest nominal IGC growth rate in the longitudinal direction (L) or long transverse direction (T) and the slowest in the short transverse direction (S). We propose a three-way intersection model and use it to simulate the corrosion kinetics for each direction. With a proper combination of model parameters, the generalized IGC model provides a good fit to experimental data developed by the foil penetration technique.     

On the trimmed mean and minimax-variance L-estimation in Kolmogorov neighbourhoods

We consider the properties of the trimmed mean, as regards minimax-variance L-estimation of a location parameter in a Kolmogorov neighbourhood K() of the normal distribution: We first review some results on the search for an L-minimax estimator in this neighbourhood, i.e. a linear combination of order statistics whose maximum variance in K_t() is a minimum in the class of L-estimators. The natural candidate – the L-estimate which is efficient for that member of K_t,() with minimum Fisher information – is known not to be a saddlepoint solution to the minimax problem. We show here that it is not a solution at all. We do this by showing that a smaller maximum variance is attained by an appropriately trimmed mean. We argue that this trimmed mean, as well as being computationally simple – much simpler than the efficient L-estimate referred to above, and simpler than the minimax M- and R-estimators – is at least “nearly” minimax.     

Random regression models for human immunodeficiency virus ribonucleic acid data subject to left censoring and informative drop-outs

Objectives in many longitudinal studies of individuals infected with the human immunodeficiency virus (HIV) include the estimation of population average trajectories of HIV ribonucleic acid (RNA) over time and tests for differences in trajectory across subgroups. Special features that are often inherent in the underlying data include a tendency for some HIV RNA levels to be below an assay detection limit, and for individuals with high initial levels or high ranges of change to drop out of the study early because of illness or death. We develop a likelihood for the observed data that incorporates both of these features. Informative drop-outs are handled by means of an approach previously published by Schluchter. Using data from the HIV Epidemiology Research Study, we implement a maximum likelihood procedure to estimate initial HIV RNA levels and slopes within a population, compare these parameters across subgroups of HIV-infected women and illustrate the importance of appropriate treatment of left censoring and informative drop-outs. We also assess model assumptions and consider the prediction of random intercepts and slopes in this setting. The results suggest that marked bias in estimates of fixed effects, variance components and standard errors in the analysis of HIV RNA data might be avoided by the use of methods like those illustrated.