Non-parametric inference for ordered alternatives in a randomized block design

This paper treats the problem of testing an ordered hypothesis based on the ranks of the data. The statistical procedures for the randomized block design with more than one observation per cell are derived. Multiple comparisons and estimation procedures are also included.     

Smoking onset in adolescence: a person-centered analysis with time-varying predictors.

Predictions from smoking-specific versus contextual models of smoking onset were tested with data from a 4-wave sample with 1,364 adolescents. Predictor variables were derived from stress-coping theory, social influence theory, and problem-behavior theory. In addition to groups of abstainers and experimenters, cluster analysis of smoking data indicated 3 groups who showed onset either in 7th grade (early onset), 9th grade (intermediate onset), or 10th grade (late onset). Almost all study variables discriminated the smoking groups from the abstainers. The onset groups were discriminated by Group X Time interactions showing differential changes in predictors (increases in risk factors and declines in protective factors), which occurred just prior to onset. The results generally support a contextual model of the onset process.     

Reliability and sensitivity of suicide certification in higher-income countries.

World Health Organization age-, sex-, and cause-specific mortality data for the United States and 19 other democratic higher-income countries were utilized to assess the reliability and sensitivity of suicide certification for purposes of cross-national research. Data are found to be highly reliable across age and sex (rs > 0.92; P < 0.001). Relative discrepancies between official suicide rates (putative lower limits) and projected upper limits vary widely internationally. Austrian and Dutch suicide certification is the most sensitive. Least sensitive is certification for certain subpopulations in Finland, Greece, Ireland, Israel, and the United Kingdom. We recommend similar analyses be performed for routine, low-cost surveillance of suicide data quality, and to guide choice of population groups for multivariate comparative research.     

The effects of preoperative preparation on postoperative outcomes: the moderating role of control appraisals.

OBJECTIVE: To test the proposal that external health locus of control and self-efficacy would moderate the effects of a psychological preparation for surgery on outcomes for surgical heart patients. MAIN OUTCOME MEASURES: Psychological distress, pain, serum cortisol, and tumor necrosis factor alpha. DESIGN: A total of 80 coronary artery bypass graft patients were given standard care plus a psychological preparation or standard care alone using a single-blind methodology with random assignment. Data on psychological and biological functioning were collected at admission (baseline) and discharge. RESULTS: As predicted, external health locus of control and self-efficacy moderated the effect of the preparation on all outcomes. Results indicated that for high external health locus of control, the preparation was related to lower distress for people with high self-efficacy compared with those with low self-efficacy. When external health locus of control was low, the preparation was related to lower distress for those with lower self-efficacy. CONCLUSION: These findings caution against the use of preparations and education for surgical patients without accounting for control appraisals.     

Believers and Their Disbelief

Several recent Roman Catholics who were known for their devotion have left accounts of their troubled faith. I consider three of these: St. Therese of Lisieux, Mother Teresa of Calcutta, and Pierre Teilhard de Chardin. Then I tell of the troubled atheism of Jean‐Paul Sartre. Finally, I use texts of Sartre and Teilhard to understand the unsettled nature of belief.     

Media use and school achievement – boys at risk?

In work done at the German Criminological Research Institute of Lower Saxony (KFN) various methods have been used to investigate how specific inappropriate media usage patterns affect academic performance in children and adolescents. The findings are paralleled by current international research indicating a negative relationship between these two variables. Based on a cross‐sectional survey of 5,529 fourth grade students and a longitudinal panel study with 1,157 primary schoolchildren, a key finding can be demonstrated: the more time students spend on consuming media and the more violent its contents are, the worse are their marks at school, even when controlling for vital factors such as family, educational, or immigrant background. In particular, boys who gender‐specifically are better equipped with electronic media devices, who partially have extensive media usage times and who strongly prefer violent media content, are at the risk of showing poor school performance. In fact, a decrease in academic performance of boys can be observed in German school statistics. By presenting first results of a school‐based intervention programme, a promising approach to the reduction of detrimental effects of electronic media use on school performance is introduced.     

A specific calculating ability

We report two experiments that investigate the calculating strategy used by a low IQ savant to identify prime numbers. Hermelin and O'Connor (1990) had suggested previously that this subject may use a procedure first described by Eratosthenes to detect a prime number, namely, dividing a target number by all primes up to the square root of the target number and testing for a remainder. In the first experiment, we compare the reaction times of the savant to decide whether a number is prime with those of a control subject proficient in mathematical calculation. In addition, we measured the savant's speed of information processing using an inspection time task. We found that the reaction times of the savant, although generally faster, followed the same pattern of the control subject who reported using the Eratosthenes procedure. The savant's inspection time indicated that his speed of processing was far superior to that expected from someone of his IQ. In the second experiment, we measured the time it takes mathematics students to divide by different prime numbers and we also tested them on the prime identification task. We used their division times to simulate their performance on the prime number identification task under the assumption that they used the Eratosthenes procedure. We also simulated the reaction times that would result from a simple memory-based procedure for identifying primes. We found that the Eratosthenes simulation, in contrast to the memory simulation, provided a good fit to both the students' and the savant's reaction times. We conclude that the savant is using a complex computational algorithm to identify primes and suggest two explanations of how the apparent contradiction between his low general intelligence and his superior numerical ability might be resolved.     

Genetic and Environmental Influences on the Continuous Scales of the Myers-Briggs Type Indicator: An Analysis Based on Twins Reared Apart

The Myers-Briggs Type Indicator was administered to a sample of 61 monozygotic twins reared apart (MZA), 49 dizygotic twins reared apart (DZA), and 92 spouses, who participated in the Minnesota Study of Twins Reared Apart (MISTRA) from 1979 to 1995. Twins' scores on the continuous scales were subjected to behavior genetic model-fitting procedures. Extraversion-Introversion and Thinking-Feeling yielded heritabilities of about .60, consisting largely of nonadditive genetic variance. Sensing-Intuition and Judgment-Perception yielded heritabilities of about .40, consisting largely of additive genetic variance. Spouse correlations for three of the four scales were near zero and not statistically significant; one spouse correlation (Sensing-Intuition) was modestly positive and statistically significant.