Exact procedures for the analysis of multidimensional contingency tables

The log-linear model for contingency tables expresses the logarithm of a cell frequency as an additive function of main effects, interactions, etc., in a way formally identical with an analysis of variance model. Exact statistical tests are developed to test hypotheses that specific effects or sets of effects are zero, yielding procedures for exploring relationships among qualitative variables which are suitable for small samples. The tests are analogous to Fisher's exact test for a 2 × 2 contingency table. Given a hypothesis, the exact probability of the obtained table is determined, conditional on fixed marginals or other functions of the cell frequencies. The sum of the probabilities of the obtained table and of all less probable ones is the exact probability to be considered in testing the null hypothesis. Procedures for obtaining exact probabilities are explained in detail, with examples given.     

External Validity of Conduct and Oppositional Defiant Disorders Determined by the NIMH Diagnostic Interview Schedule for Children

We administered the Diagnostic Interview Schedule for Children (DISC) two times to a group of youth (222 boys, 147 girls) entering residential care, once at their time of entry and once 1 year later. We then compared their DISC outcomes on Conduct Disorder (CD) and Oppositional Defiant Disorder (ODD) against changes in independent direct observations of diagnostically relevant behavior obtained over the course of that year. Results from hierarchical linear modeling analyses showed significant discriminative relationships between results from the DISC and the independent observations. Specifically, observations of symptomatic behaviors (CD or ODD) decreased for youth who met diagnostic criteria at the first administration of the DISC but not at the second, increased for youth who did not meet criteria at the first administration but did at the second, and did not change for youth who met criteria at both administrations. These results extend the data on the validity of the DISC and support continued research efforts to determine its clinical utility.     

Physical and mental health trajectories of cancer patients and caregivers across the year post-diagnosis: a dyadic investigation

Objective: Evidence suggests interdependence between cancer patients’ and their caregivers’ physical and mental health. However, the extent to which caregivers’ health relates to their patients’ recovery, or patients’ health affects their caregivers’ outcomes, is largely unknown. This dyadic investigation reports the relations between cancer patients’ and their caregivers’ physical and mental health trajectories during the year following diagnosis.

Design: Ninety-two colorectal cancer patient–caregiver dyads completed questionnaires at 2, 6 and 12 months post-diagnosis.

Outcome measures: Self-reported physical and mental health using the Medical Outcomes Study Short Form Health Survey-12.

Results: Patients reported improved physical health over the year following their diagnosis, whereas caregivers reported declining physical health. Patients with lower mental health at diagnosis had stagnated physical health recovery. Caregivers’ physical health declined most noticeably among those reporting low mental health at diagnosis and whose patients reported low physical health at diagnosis.

Conclusion: Findings suggest targeting health interventions to cancer patients and caregivers reporting poor mental health at diagnosis may mitigate their long-term physical morbidity. Limited evidence of dyadic interdependence between patients’ and caregivers’ physical and mental health trajectories suggests future studies are warranted to identify psychosocial and medical characteristics moderating the relations between patients’ and caregivers’ health.     

Evidence for a generic interceptive strategy

In the present work, we first clarify a more precise definition of instantaneous optical angles in control tasks such as interception. We then test how well two interceptive strategies that have been proposed for catching fly balls account for human Frisbee-catching behavior. The first strategy is to maintain the ball's image along a linear optical trajectory (LOT). The second is to keep vertical optical ball velocity decreasing while maintaining constant lateral optical velocity. We found that an LOT accounted for an average of over 96% of the variance in optical Frisbee movement, while maintenance of vertical and lateral optical velocities was random. This work confirms a common interception strategy used across interceptive tasks, extending to complex target trajectories.     

Rorschach Comprehensive System data for a sample of 42 nonpatient Mexican American children from the United States

This study is composed of 42 Mexican American children, ages 8 to 10 years, all from the United States. In addition to the children being administered the Rorschach, they also were administered the Children's Hispanic Background Scale (CHBS) and the Children's Personality Questionnaire (CPQ). The principal author was the sole examiner. Inclusion criteria are described. Interrater reliability statistics at the response level are presented along with scores for the Rorschach Comprehensive System (CS; Exner, 1995).     

Criminality and continued DUI offense: criminal typologies and recidivism among repeat offenders

We examined over 20,000 arraignment records to define criminal typologies and post-treatment driving under the influence of alcohol (DUI) convictions for a select cohort of 1,281 repeat DUI offenders who were offered and elected treatment as an alternative to incarceration; we compared this information with a similar data analysis collected 20 years previously. Analyses of 8,600 prior-to-treatment convictions defined four basic crime profiles: only DUI and other substance-related offenses (60%), plus crimes against property (18%), plus crimes against people (8%), plus crimes against both property and people (13%). During the six years after inpatient treatment, 15.5% of the cohort was convicted of another DUI. The reoffense rate was significantly different across criminal types and was not related to the time post treatment years at risk. The findings show there has been no significant improvement in treatment outcome over the last 20 years. New and innovative DUI offender policies and practices are needed to better engage the heterogeneous offender population, and reduce the incidence of repeat DUI.     

"IF YOU LET ME PLAY SPORTS"

This study tests a model specifying that girls' precollege participation in sporting activities will foster positive body images, enhanced perceptions of physical competence, and more flexible gender identities, which, in turn, predict higher college self-esteem. A sample of 220 college females (mean age = 19.65 years) provided retrospective reports of their precollege sport involvement and contemporaneous assessments of body image, perceived physical competencies, gender identity, global self-esteem, and other psychosocial variables. Consistent with prior reports on male and mixed-gender samples, greater precollege sport participation predicted higher self-esteem in this exclusively female sample. Follow-up path analyses and tests for mediation revealed that the model's intervening variables totally mediated the sport participation/self-esteem relationship. The patterning of these data implies that participating in sports promotes females' self-worth by fostering physical competencies, favorable body images, and gender flexibility, and, in the absence of any such psychosocial benefits, participation in sports has little salutary effect on and can even undermine self-esteem.     

Timing in solo and duet piano performances

Perhaps some of the most refined forms of timing arise in musical performance, particularly in the coordination between musicians playing together. Studies of timing in solo and duet piano performances are described, in which the musicians gave repeat performances of the music. In both solo and duet performances there was expressive use of timing, modulating the tempo of the music and the phase relationship between the voices, and the expressive forms were similar in successive performances of the piece. There was also evidence of separate timing control of the metre and of the production of notes and rests. Thus timing in musical performance is best modelled by assuming two levels of timekeeper, one pacing the metre and the other contained in the movement trajectories of note production, computed by motor procedure in relation to the metre. It is argued that expressive forms are derived from an interpretation of the music rather than memorized; and that coordination between voices in the music is achieved at the level of the metre.