Donald A. Rock

The Use Of Analysis Of Covariance Structures For Comparing The Psychometric Properties Of Multiple Variables Across Populations

It is common practice to assume that the dependent variables in differential prediction studies, and analysis of variance and co-variance designs are characterized by certain psychometric properties which are invariant across the subgroups of interest. More specifically, the accuracy of the results of such analyses depends on the assumption that the dependent variables are measuring the constructs in the same metrics with equivalent reliabilities across all subgroups. Systematic procedures are outlined for testing these assumptions.

Sex differences in predictions of college grades from Scholastic Aptitude Test scores

In this study we appraised 2 explanations for sex differences in over- and underprediction of college grades by the Scholastic Aptitude Test: sex-related differences in (a) the nature of the grade criterion and (b) the variables associated with academic performance. An entire freshman class at a large state university was studied. Womens grade point average (GPA) was underpredicted (and mens GPA was overpredicted), but only by a small amount. When we adjusted the GPA for differences in grading standards for individual courses, over- and underprediction were not affected, but when we controlled for sex differences in individual-differences variables concerned with academic preparation, studiousness, and attitudes about mathematics, over- and underprediction were reduced

The New York high-risk project: social and general intelligence in children at risk for schizophrenia

UNLABELLED Social deficits, as well as low performance on intelligence tests, are known early symptoms of schizophrenia. We studied whether impairment of social intelligence can be detected before the outbreak of the disorder. In the New York High-Risk Project, children at risk for schizophrenia (HRSz) or affective disorder (HRAff) and a normal control group (NC) were studied over the past 26 years. The children are now in mid-adulthood, with known psychiatric outcomes. Developmental and clinical data from childhood can now be related to adulthood diagnoses. We compared mean WISC (or WISC-R) and WAIS (or WAIS-R) scores from childhood and adolescence, and change of IQ, between the risk groups, as well as between the adulthood outcomes. We were specifically interested in the development of social intelligence (the Picture Arrangement and Comprehension subtests). We used logistic regression analyses to generate a model predicting adulthood schizophrenia. RESULTS IQ at age 9,7 was lower in children with HRSz than with HRAff. Adulthood schizophrenia, compared with major depressive disorder and no psychiatric diagnosis could not be related conclusively to low IQ. This may be a result of the study design, since children with IQ below 70 or behavioral problems were not eligible as study subjects. There was no evidence of lower scores or more decline in social intelligence related to age or group membership (risk or outcome). Subtest-Scatter, a nondirectional measure of the differences between all subtests and Vocabulary, reflecting a lesser difference between crystallized and fluid intelligence, was identified as a significant predictor of adulthood schizophrenia, in the whole group as well as in the HRSz group alone.

Positive and negative thought disorder and psychopathology in childhood among subjects with adulthood schizophrenia

UNLABELLED The New York High-Risk Project (NYHRP) is a longitudinal study of offspring of parents with schizophrenia or affective disorder and normal controls. Neuropsychological deficits had been observed at about age 9 in subjects with adulthood schizophrenia. We explored whether in these subjects, early signs of clinical schizophrenia-related symptoms, such as thought disorder or behavioral abnormalities, could also be observed. METHODS We rated thought disorder and symptoms from videotaped interviews at age 9, using the Scale for the Assessment of Thought, Language and Communication (TLC), and the Mental Health Assessment Form (MHAF). With factor analyses we examined the structure of the ratings, and from interpretable factors, scales were assembled. MANOVAs were used to examine the effect of parental risk and adulthood psychiatric diagnosis (schizophrenia-related psychosis (SRP), major affective disorder (MAD), no disorder/other (NoDx/other)) as independent variables (IV) on thought disorder and symptoms as dependent variables. RESULTS Global, positive and negative thought disorder, and negative symptoms were significantly higher in subjects with adulthood schizophrenia-related psychosis than both comparison groups. A significant interaction between the two IVs was effective with respect to positive thought disorder. This scale was particularly elevated among subjects with adulthood schizophrenia-related psychosis at parental risk for affective disorder (all of whom had adulthood schizoaffective disorder). CONCLUSIONS We were able to show that global, negative and positive thought disorder and negative symptoms were present in subjects with adulthood schizophrenia already at mid-childhood, years before onset of psychosis. Further, we found a particularly high propensity to positive symptoms in subjects with adulthood schizophrenia who have also an affective component in their symptoms. This association, previously reported in acute schizophrenia, was here observed years before the first psychotic episode.

Relationships between College Characteristics and Student Achievement.

As greater numbers of young people continue on to college, it becomes of increasing concern to know which institutional characteristics are associated with how much a student learns during his four years in college. Such information is important not only to the theorist who is attempting to understand how and to what extent college characteristics influence student behavior, but to the college administrator who requires such information for decisions concerning the optimum allocation of limited funds among many competing educational programs and processes. In addition, the recent increase in student population has been accompanied by an ever increasing flow of both public and private funds into the college system, resulting in an increasing need to evaluate the potential payoff of differential funding policies. Many of the differences among colleges with respect to their resources have been documented by Astin and Holland (1962), Cartter (1964), and the College Data Bank of Columbias Bureau of Applied Social Research (1966). However, little additional light has been shed on whether or not these differences are associated with differential student achievement. Certainly any study of the impact of various

Early life precursors of psychiatric outcomes in adulthood in subjects at risk for schizophrenia or affective disorders

In the New York High-Risk Project (NYHRP), 186 offspring of schizophrenic, affectively ill, and psychiatrically normal parents have been followed prospectively from 1971-72 to the average age of 27 years in 1990 with the goal of identifying early precursors of later psychopathology. In this report, we use path analyses to examine the relationship of several life-history variables to three pathological outcomes in the offspring: namely, psychosis, psychiatric hospitalization, and psychological dysfunction. The chief direct relationship with these outcomes is the effect of having a schizophrenic parent. The latter effect is also mediated indirectly by IQ.

Agreement between expert-system and human raters' scores on complex constructed-response quantitative items.

This study evaluated agreement betwen expert-system and human scores on 12 constructed-response algebra word problems taken by Graduate Record Examination General Test examinees. Ideas are discussed for using expert systems in large-scale assessment programs and in interactive diagnostic assessment.

The Development and Evaluation of Several Programmed Testing Methods.

papers (Cleary, Linn, and Rock, 1968a, 1968b). A programmed test has been defined as a test in which the presentation of test items is contingent upon the previous responses of the examinee. Although not well suited to the present paper-and-pencil technology of the testing industry, programmed tests are being made more feasible by improved use of computer hardware. The flexibility and the possibility of reduced testing time are the major appeals of programmed tests.

The Relationship of Expert-System Scored Constrained Free-Response Items to Multiple-Choice and Open-Ended Items

This study examined the relationship of an expert- system scored constrained free-response item (requir ing the student to debug a faulty computer program) to two other item types: (1) multiple-choice and (2) free- response (requiring production of a program). Confir matory factor analysis was used to test the fit of a three-factor model to these data and to compare the fit of the model to three alternatives. These models were fit using two random-half samples, one given a faulty program containing one bug and the other a program with three bugs. A single-factor model best fit the data for the sample taking the one-bug constrained free re sponse and a two-factor model fit the data somewhat better for the second sample. In addition, the factor intercorrelations showed this item type to be highly re lated to both the free-response and multiple-choice measures.

Assessing leadership potential with a biographical measure of personality traits.

The aim of this study was to demonstrate the feasibility of biographical inventories free of the limitations common to many current biographical measures by constructing and validating an inventory composed of homogeneous scales, with item content that is factual and fair, to assess personality traits predictive of leadership. The experimental inventory, with tentative scales for Dominance, Emotional Stability, Need for Achievement, Self-Confidence, and Sociability, was administered to incoming midshipmen at the US Naval Academy and item analyzed. The validity of the final scales was appraised against subsequent peer ratings of the traits and of leadership shortly after entering the Academy; military performance grades, and midshipman rank and leadership position at the Academy; and recommendations for promotion after graduating and serving as an officer. The Sociability, Dominance, and Need for Achievement scales demonstrated convergent and discriminant validity, and all of the scales except Self-Confidence correlated with the leadership criteria. The Sociability scale’s consistent correlations with several of the leadership criteria, including a nontrivial correlation (r = 0.28) with the leadership peer rating, implies that this measure may be useful in assessing leadership potential.