Representativeness in the Market for Bets on National Football League Games

In laboratory experiments the representativeness heuristic has been shown to affect participants' judgments. Finding representativeness in a real-world economic market would indicate that even decision makers who are highly experienced and motivated use the heuristic, and would, in addition, violate the efficient market hypotheses, i.e. the theory that market prices fully reflect all available information. Testing for representativeness in the market for bets on National Football Leagues games avoids complications that make tests of representativeness in a stock market difficult to interpret. Evidence for representativeness in the NFL betting market is found in a data set from an earlier study which failed to test for representativeness, and in the 1976– 9 market. Representativeness does not appear to exist in the contemporary market, however, perhaps because with the advent of the personal computer the market depends less on purely human judgment.     

Young Israelis' Reactions to National Trauma: The Rabin Assassination andTerror Attacks

This study examined the cognitive and emotional reactions of 477 Israeli high school students to the assassination of Prime Minister Yitzhak Rabin (immediately after the event as well as 5 months later) and to a series of terror attacks. The respondents' reactions to the two events were compared as a function of gender and political orientation. About 50% of the respondents who changed their political views immediately after the assassination reverted to pre-event attitudes 5 months later. Emotional reactions to the assassination showed substantial fading after 5 months, with extent of fading unaffected by gender or political orientation. The intensity of emotional reactions was affected by political orientation: Although Rabin's supporters and his opponents reacted with equal intensity to the terror attacks, supporters reacted with the same intensity to Rabin's assassination, whereas opponents' reactions to the assassination were less intense.     

Evoked potential and visual half-field evidence for task-dependent cerebral asymmetries in congenitally deaf adults

Evoked potentials to laterally presented stimuli were collected from left and right tempero-parietal sites during performance of two visual half-field tasks, lexical decision, and line orientation discrimination. Reaction time and accuracy data were simultaneously collected. The behavioral data indicated the development of a right field advantage for the lexical decision task as a function of practice. A principal components analysis revealed three independent evoked potential components which displayed task-dependent hemispheric asymmetries. Multiple regression analyses revealed that visual half-field asymmetries in response accuracy were closely related to hemispheric asymmetries on several independent evoked response components. Subject's scores on independent tests of verbal reasoning and spatial relations were also found to be closely related to hemispheric asymmetry on several independent evoked response components. These data support a multidimensional concept of cerebral specialization. They also suggest that visual field asymmetries reflect the confluence of several underlying processes which have independent lateralization distributions across the population. In general, the results underscore the need for further research on the nature of the relationship between cerebral and perceptual asymmetries.     

Conflicting codes: Professional, ethical, and legal obligations in archaeology

Archaeologists employed in governmental positions often deal with issues that produce conflicts between their professional duties to their employer, their ethical responsibilities to the resource, and their obligations as established by legislation. The paper examines some of the conflicts imposed on governmental archaeologists by each of these systems but focuses on the conflicts imposed by federal legislation and regulations on governmental archaeologists, using “Kennewick Man” as an example. This is a revised edition of a paper written for the symposium: “Ethics in Science: Special Problems in Anthropology and Archaeology,” organized by Merrilee Salmon; 1998 Annual Meeting of the American Association for the Advancement of Science (Philadelphia, February 15, 1998). The original paper was in a more conversational style as befitting a discussion atmosphere. Revisions, comments, and opinions are entirely the author’s. Joe Watkins is the Anadarko Agency Archaeologist at the Bureau of Indian Affairs and is a Research Associate in the Department of Anthropology, Indiana University.     

Should “multiple imputations” be treated as “multiple indicators”?

Rubin's multiple imputation approach to missing data creates synthetic data sets, in which each missing variable is replaced by a draw from its predictive distribution, conditional on the observed data. By construction, analyses of such filled-in data sets as if the imputations were true values have the correct expectations for population parameters. In a recent paper, Mislevy showed how this approach can be applied to estimate the distributions of latent variables from complex samples. Multiple imputations for a latent variable bear a surface similarity to classical multiple indicators of a latent variable, as might be addressed in structural equation modelling or hierarchical modelling of successive stages of random sampling. This note demonstrates with a simple example why analyzing multiple imputations as if they were multiple indicators does not generally yield correct results; they must instead be analyzed by means concordant with their construction.I am grateful to Frank Jenkins, John Mazzeo, Kentaro Yamamoto, and Rebecca Zwick for comments on earlier versions of this paper.     

Social indicators as indexes of neuroticism and extraversion

Lynn and Hampson (1975) and recently Lester (2000) suggested that national level of extraversion (E) and neuroticism (N) could be assessed by using certain national indicators like suicide and divorce rates. In this study, Lynn and Hampson’s (1975) and Lester’s (2000) models were assessed by using 1990s data. Although Lynn and Hampson’s original N and E factors correlated with EPQ N (r=0.48) and E (r=0.60) scores as hypothesised, the factor structure did not recur in the 1990s data. Factor analysis supported Lester’s (2000) model of N and E. However, the factor loadings for EPQ N and E were rather modest (0.49 for N and 0.36 for E). It was concluded that more research with larger datasets and new social indicators are needed before social indicators could replace the EPQ in comparisons of national characteristics of nations.     

Children of Probationers in the Child Welfare System and Their Families

This study describes changes over a 36-month period in the lives of children of probationers who were subjects of reports of maltreatment. Data on a nationally representative sample of reported victims of maltreatment were used to examine probationer-parents’ contact with the criminal justice system, and concurrent changes in their children’s households, risk exposure, and emotional and behavioral problems. Results show that 36 months after coming in contact with the child welfare system, about 40% of probationer’s children no longer lived with their probationer-parents. During the same period, children’s exposure to risk (i.e., parental substance abuse, mental illness, and domestic violence) dropped markedly; however, there was an upward trend in the prevalence of child emotional and behavioral problems. These problems ultimately declined among very young children, but persisted among elementary school age children. Further prospective studies are needed to better understand the confluence of factors affecting the outcomes of probationers’ children.     

Expanding the g-nexus: Further evidence regarding the relations among national IQ, religiosity and national health outcomes

The current study seeks to better understand how religiosity and health are positioned within the g-nexus. Specifically, the degree to which differences in average IQ across nations is associated with differences in national religiosity (i.e., belief rate) and national health statistics independent of differences in national wealth is examined. Consistent with expectations, results show that, independent of national wealth and belief rate, IQ has a positive influence on national health as indicated by fertility rate, infant mortality rate, maternal mortality rate, and deaths due to HIV/AIDS, and life expectancy. Additionally, as hypothesized, IQ and belief rate interacted to influence reproductive health (i.e., fertility rate, infant- and maternal mortality). Specifically, high IQ acts as a buffer against the negative effects of belief rate; when IQ is high belief rate has no effect, but when IQ is low belief rate has a strong negative effect. The pattern of findings from this study, combined with previous research, serve to confirm that general cognitive ability (i.e., the g-factor) is an important and central node within a larger nexus of psychological and social variables. Theoretical and epidemiological implications are discussed.     

The predictive value of numerical magnitude comparison for individual differences in mathematics achievement

Although it has been proposed that the ability to compare numerical magnitudes is related to mathematics achievement, it is not clear whether this ability predicts individual differences in later mathematics achievement. The current study addressed this question in typically developing children by means of a longitudinal design that examined the relationship between a number comparison task assessed at the start of formal schooling (mean age = 6 years 4 months) and a general mathematics achievement test administered 1 year later. Our findings provide longitudinal evidence that the size of the individual’s distance effect, calculated on the basis of reaction times, was predictively related to mathematics achievement. Regression analyses showed that this association was independent of age, intellectual ability, and speed of number identification.     

Mutual Help Groups for Mental Health Problems: A Review of Effectiveness Studies

This paper reviews empirical studies on whether participating in mutual help groups for people with mental health problems leads to improved psychological and social functioning. To be included, studies had to satisfy four sets of criteria, covering: (1) characteristics of the group, (2) target problems, (3) outcome measures, and (4) research design. The 12 studies meeting these criteria provide limited but promising evidence that mutual help groups benefit people with three types of problems: chronic mental illness, depression/anxiety, and bereavement. Seven studies reported positive changes for those attending support groups. The strongest findings come from two randomized trials showing that the outcomes of mutual help groups were equivalent to those of substantially more costly professional interventions. Five of the 12 studies found no differences in mental health outcomes between mutual help group members and non-members; no studies showed evidence of negative effects. There was no indication that mutual help groups were differentially effective for certain types of problems. The studies varied in terms of design quality and reporting of results. More high-quality outcome research is needed to evaluate the effectiveness of mutual help groups across the spectrum of mental health problems.