James Jaccard

Components of Reading Ability: Multivariate Evidence for a Convergent Skills Model of Reading Development

Elementary and middle school children were given a large battery of tests evaluating reading subskills and reading-related cognitive abilities. These measures were used to define latent representing skills and abilities believed to be important components of reading comprehension. Hypothesized relationships among these constructs were specified within the context of a structural model we call the “Convergent Skills Model of Reading Development,” and developmental differences in the relative contribution made by each construct to reading comprehension performance were assessed through confirmatory factor analysis using the LISREL and AMOS programs. Results provide qualified support for the model and were interpreted as consistent with the major premises of both Gough and Tunmers (1986) “Simple View” and Stichts (1979) “Audread” models of reading.

Peer Influences on Risk Behavior: An Analysis of the Effects of a Close Friend.

Cross-sectional research suggests that peer influence has a moderate to strong impact on adolescent risk behavior. Such estimates may be inflated owing to third-variable confounds representing either friendship selection effects or the operation of parallel events. Approximately 1,700 peer dyads in Grades 7 to 11 were studied over a 1-year period to estimate the influence of closest friends on sexual activity and binge drinking. Analyses suggested that peer influence was small but reliable when both selection effects and parallel events were taken into account. Peer influence varied as a function of individual-peer similarity and maternal relations but not in accord with other theoretical predictions. It is suggested that the magnitude of peer effects in previous research may be overestimated in many contexts.

Who develops PTSD from motor vehicle accidents

Within 1 to 4 months of their motor vehicle accident (MVA), we assessed 158 MVA victims who sought medical attention as a result of the MVA. Using the Clinician-Administered PTSD Scale (CAPS: Blake, Weathers, Nagy, Kaloupek, Klauminzer, Charney & Keane, 1990. National Center for Post-Traumatic Stress Disorder, Boston, MA)., we found that 62 (39%) met DSM-III-R (American Psychiatric Association, 1987. Washington, DC: American Psychiatric Press) criteria for Post-Traumatic Stress Disorder. Using variables from the victims account of the accident and its sequelae, pre-MVA psychosocial functioning, demographic variables, pre-MVA psychopathology and degree of physical injury, we found that 70% of the subjects could be classified as PTSD or not with 4 variables: prior major depression, fear of dying in the MVA, extent of physical injury and whether litigation had been initiated. Using multiple regression to predict the continuous variable of total CAPS score, as a measure of post-traumatic stress symptoms, we found that 8 variables combined to predict 38.1% of variance (Multiple R = 0.617).

Variables that moderate the attitude–behavior relation: Results of a longitudinal survey.

The following factors were hypothesized to moderate the attitude-behavior relation: (a) the behavioral sequence that must be successfully completed prior to the occurrence of the behavior, (b) the time interval between the measurement of attitudes and behavior, (c) attitude change, (d) the respondents educational level, and (e) the degree of correspondence between attitudinal and behavioral variables. The behaviors investigated were having a child and using oral contraceptives. A stratified random sample of 244 married women in a midwestern urban area was studied during a three-wave, 2-year longitudinal study. Selection of attitudinal and belief measures was guided by the Fishbein model of behavioral intentions. Consistent with the hypotheses, the relations between behavior and both intention and the models attitudinal and normative components were substantially attenuated by (a) events in the behavioral sequence not under the volitional control of the actor, (b) an increase in the time interval between the measurement of attitudes and behavior from 1 to 2 years, and (c) changes in the models attitudinal and normative components during the first year. The respondents educational level did not affect attitudebehavior consistency. Finally, the attitude-behavior correlation increased significantly as the degree of correspondence between the two variables increased.

Analysis of variance frameworks in clinical child and adolescent psychology: Advanced issues and recommendations.

Explores more advanced issues that researchers need to consider when using analysis of variance frameworks, building on basic issues for analysis of variance discussed in Jaccard and Guilamo-Ramos (2002). These include (a) using confidence intervals, (b) asserting group equivalence after a nonsignificant result, (c) use of magnitude estimation approaches, (d) sample size and power considerations, (e) outlier analysis, (f) violations of assumptions, and (g) missing data. Suggestions are offered for analytic practices in each of these domains.

Cross‐cultural model testing: toward a solution of the etic‐emic dilemma

Abstract A model for the prediction of behavior from attitudinal components, developed by Triandis, was tested with samples of U.S. and Mexican women, and with fertility relevant behaviors. The elements of the model are etic, but the opera-tionalizations of the various variables were done emically. Results support the model in both cultures. While the predictive utility of the model is equivalent in two cultures, there are social class differences on which component of the model is most emphasized. The U.S. upper-middle-class sample and the Mexican upper-middle-class sample emphasized the persons attitude toward the act, while the Mexican lower SES (socio-economic status) sample emphasized the persons normative beliefs (moral obligations).

Psychological aspects of organ donation: a critical review and synthesis of individual and next-of-kin donation decisions.

This article presents a critical review of psychological perspectives on organ donation. The review considers individual decisions to donate organs posthumously and next-of-kin consent decisions. A theoretical analysis of intention to donate is presented for both types of donation decisions, and the literature is reviewed within the context of the proposed framework. Donation decisions are examined as a function of attitude toward donation and the religious, cultural, altruistic, normative, and knowledge-based beliefs that comprise the attitude. Consent decisions are primarily influenced by prior knowledge of the deceased individuals wishes. An alternative conceptual model is offered to explain the basis of consent decisions in the absence of this knowledge. Suggestions are offered to improve measurement strategy and to guide theoretically based organ donation research within selected disciplines of psychology.

Examination of the short-term efficacy of a parent intervention to reduce college student drinking tendencies.

The research evaluated the efficacy of an intervention to reduce the onset and extent of binge drinking during the 1st year of college. The approach was on influencing the students before they start college, through their parents, during the critical time between high school graduation and the beginning of college. Specifically, parents were educated about binge drinking and how to convey information to their teens, and then encouraged to talk with their teens just before their teens embarked on their college education. Teens whose parents implemented the intervention materials were compared with a control sample during their 1st semester on drinking outcomes, perceptions about drinking activities, perceived parental and peer approval of drinking, and drinking-related consequences. As anticipated, teens in the treatment condition were significantly different (p < .05) on nearly all outcomes in the predicted directions (e.g., lower drinking tendencies, drinking consequences). The benefits of a parent-based intervention to prevent college drinking are discussed.

Assessing Attribute Importance: A Comparison of Six Methods

Six methods of measuring attribute importance were evaluated for convergent validity. The methods were (1) an open-ended elicitation approach, (2) an information-search approach based on Jacobys behavioral process technology, (3) direct ratings of importance, (4) conjoint measurement, (5) indices based on Jaccards subjective probability approach, and (6) a paired comparison approach. The convergent validity of importance methods was investigated for two product classes: birth control and cars. Results indicated relatively low levels of convergence among measures.

Predicting ethnic and racial discrimination: a meta-analysis of IAT criterion studies.

This article reports a meta-analysis of studies examining the predictive validity of the Implicit Association Test (IAT) and explicit measures of bias for a wide range of criterion measures of discrimination. The meta-analysis estimates the heterogeneity of effects within and across 2 domains of intergroup bias (interracial and interethnic), 6 criterion categories (interpersonal behavior, person perception, policy preference, microbehavior, response time, and brain activity), 2 versions of the IAT (stereotype and attitude IATs), 3 strategies for measuring explicit bias (feeling thermometers, multi-item explicit measures such as the Modern Racism Scale, and ad hoc measures of intergroup attitudes and stereotypes), and 4 criterion-scoring methods (computed majority-minority difference scores, relative majority-minority ratings, minority-only ratings, and majority-only ratings). IATs were poor predictors of every criterion category other than brain activity, and the IATs performed no better than simple explicit measures. These results have important implications for the construct validity of IATs, for competing theories of prejudice and attitude-behavior relations, and for measuring and modeling prejudice and discrimination.