Latent Class Factor and Cluster Models, Bi-Plots, and Related Graphical Displays

We propose an alternative method of conducting exploratory latent class analysis that utilizes latent class factor models, and compare it to the more traditional approach based on latent class cluster models. We show that when formulated in terms of R mutually independent, dichotomous latent factors, the LC factor model has the same number of distinct parameters as an LC cluster model with R+1 clusters. Analyses over several data sets suggest that LC factor models typically fit data better and provide results that are easier to interpret than the corresponding LC cluster models. We also introduce a new graphical "bi-plot" display for LC factor models and compare it to similar plots used in correspondence analysis and to a barycentric coordinate display for LC cluster models. New results on identification of LC models are also presented. We conclude by describing various model extensions and an approach for eliminating boundary solutions in identified and unidentified LC models, which we have implemented in a new computer program.     

Life and Work Values of Counselor Trainees: A National Survey

This national web‐based study used the Schwartz Value Survey (Schwartz, 1994) and Super's Work Values Inventory‐Revised (Zytowski, n.d.) to identify general life and work value orientations of 674 female and male entry‐level counselor trainees residing in 27 states. In general, trainees emphasized benevolence, self‐direction, and achievement and the work values lifestyle, supervision, and achievement. Significant multivariate and univariate differences for age, gender, and program of study were found on both value domains. The sample of practicing counselors scored significantly higher on several values than did trainees. Implications for how students construe values to develop toward their professional role of counselor are considered.     

Appearance-Based Trait Inferences and Voting: Evolutionary Roots and Implications for Leadership

This paper examines the evolutionary roots of research findings that demonstrate that rapid judgments of political candidates’ faces predict electoral success. Also discussed are the implications of these findings for the election and selection of leaders. We argue that rapid judgments of facial competence are a result of immediate, automatic assessment of the strength of a target, reflected in facial cues of dominance/threat; and assessment of facial cues of trust/approachability. As a result, research participants and uninvolved voters select the same candidates—those that appear relatively strong and trustworthy at a glance. The votes of highly involved voters are not influenced by such facial qualities.     

Beyond the stereotypical implications of terrorism: a sociological investigation of Arab immigrants

Post 11 September 2001, terrorism has emerged as the defining stereotype of Arab immigrants. As a result, the study of Arab immigrants has become susceptible to stereotypes because in an era of unprecedented diversity sociological investigation has neglected spirituality. Among the various Arab populations spirituality is fundamental. Subsequently any investigation of Arab immigrants is impossible without acknowledgement of a spiritual dimension in the form of Islam. Moving beyond the stereotypical implications of terrorism will require Western sovereignties to be more informed about the Arab culture. Otherwise, their lack of effort will destine the uninformed to the stereotypical implications of terrorism that will not be limited to Arab immigrants but extend to other populations as well.     

A DYNAMIC PROCESS MODEL OF DISSATISFACTION FOR UNFAVORABLE,NON-ROUTINE SERVICE ENCOUNTERS

This paper explores the effect of expectations and information on customer dissatisfaction in unfavorable, nonroutine service encounters. In complex services (e.g., health care) with multiple encounters and wide range of services, customers use some of the services rarely or only once. In such encounters, customers may not have clear expectations regarding the process and/or outcome of the impending service delivery. This may increase the likelihood of the customer to perceive poor service or be dissatisfied. Hypotheses regarding the nature of expectations—levels, uncertainty, consistency—and its affects on customer dissatisfaction are tested using a dynamic process model of customer dissatisfaction.     

Mycotoxins were not associated with environmental enteropathy in a cohort of Tanzanian children

Enteropathy is a pathophysiological condition characterized by decreased intestinal barrier function and absorption. Past studies have hypothesized that mycotoxins might impair children's growth by causing intestinal enteropathy, including interactions between mycotoxins and pathogens. We investigated the association of two mycotoxins, aflatoxin B₁ (AFB₁) and fumonisin B₁ (FB₁), independently and in conjunction with microbial pathogens, with fecal biomarkers of environmental enteropathy in children. As part of a larger MAL-ED study, 196 children were recruited in Haydom, Tanzania, and followed for the first 36 months of life. The gut inflammation biomarkers myeloperoxidase (MPO), neopterin (NEO), and alpha-1-antitrypsin (A1AT) were analyzed in stool samples at 24 months; with mean concentrations 5332.5 ng/L MPO, 807.2 nmol/L NEO, and 0.18 mg/g A1AT. Forty-eight children were measured for AFB₁-lys, with a mean of 5.30 (95% CI: 3.93-6.66) pg/mg albumin; and 87 were measured for FB₁, with a mean of 1.25 (95% CI: 0.72–1.76) ng/ml urine. Although the pathogens adenovirus and Campylobacter were associated with A1AT (p = 0.049) and NEO (p = 0.004), respectively, no association was observed between aflatoxin (MPO, p = 0.30; NEO, p = 0.08; A1AT, p = 0.24) or fumonisin (MPO, p = 0.38; NEO, p = 0.65; A1AT, p = 0.20) exposure and any gut inflammation biomarkers; nor were interactive effects found between mycotoxins and pathogens in contributing to intestinal enteropathy in this cohort. Although further studies are needed to confirm these results, it is possible that mycotoxins contribute to child growth impairment via mechanisms other than disrupting children's intestinal function.     

Using real-time simulations to make medical technology decisions

Study how one health care organization evaluated various vendors of evidence-based content for making clinical decisions.     

Counting women's labour: a reanalysis of children's net production using Cain's data from a Bangladeshi village

The economic contribution of children to their parents' households has long interested demographers because of its potential to influence fertility levels. Valuing children's labour in pre-industrial economies, however, is inherently difficult. The same is true of women's labour, a crucial component of any analysis of net production. Here we use Mead Cain's seminal study (Population and Development Review 3(3): 201-227, 1977) of children's economic contributions in a Bangladeshi village to illustrate these points. We combine Cain's data on landless women's and men's hours of work with data on the efficiency per hour of work from other pre-industrial settings (Mueller, Population and Development: The Search for Selective Interventions. Baltimore, MD: Johns Hopkins University Press, pp. 98-153, 1976; Kramer, Dissertation, Department of Anthropology, University of New Mexico, 1998). When women's labour is incorporated, we find that the Bangladeshi children begin to produce as much as they consume by ages 10 (girls) or 11 (boys). Despite these productive contributions, neither women nor men 'pay' for their cumulative consumption until their early 20s. We believe our methods could be usefully applied in other contexts.