Multiple regression analyses in artificial-grammar learning: the importance of control groups

In artificial-grammar learning, it is crucial to ensure that above-chance performance in the test stage is due to learning in the training stage but not due to judgemental biases. Here we argue that multiple regression analysis can be successfully combined with the use of control groups to assess whether participants were able to transfer knowledge acquired during training when making judgements about test stimuli. We compared the regression weights of judgements in a transfer condition (training and test strings were constructed by the same grammar but with different letters) with those in a control condition. Predictors were identical in both conditions-judgements of control participants were treated as if they were based on knowledge gained in a standard training stage. The results of this experiment as well as reanalyses of a former study support the usefulness of our approach.     

Reactions to and Desire for Prognostic Testing in Choroidal Melanoma Patients

To determine if choroidal melanoma patients want cytogenetic prognostic information. Ninety-nine choroidal melanoma patients completed a questionnaire regarding their opinions about receiving prognostic information. The perceived usefulness of prognostic information was evaluated in patients who had undergone cytogenetic testing. Depressive symptoms, quality of life, and interest in supportive counseling during test receipt were assessed. Ninety-seven percent of respondents reported that they would have wanted prognostic information at the time of their treatment and 98% of respondents reported that supportive counseling should be offered when prognostic information is given. Patients who had received a more favorable prognostic result were more likely to endorse the usefulness of cytogenetic testing than were patients who had received a less favorable prognostic result. Psychological status did not vary significantly as a function of cytogenetic test result. Prognostic information was important to patients with choroidal melanoma, even in the absence of prophylactic measures which might improve prognosis.     

Responding under time pressure: Testing two animal learning models and a model of visual categorization

Two experiments are reported, which employed a Pavlovian eyelid conditioning procedure with human participants. The experiments tested the predictions of three models of the time-course of processing under time pressure. These were the extended generalized context model (Lamberts, 1998), and two variants of the Rescorla-Wagner model (Rescorla & Wagner, 1972), which were activated in cascade mode. Reinforcement schedules in the experiments were equivalent either to an AND rule or to an XOR rule. The time available for processing the conditioned stimulus and initiating a conditioned response was manipulated by varying the interval from the onset of the conditioned stimulus to the onset of the unconditioned stimulus. The results were in accord with the predictions of one of the two variants of the Rescorla-Wagner model.     

Covariance structure analysis in experimental research: Comparing two word translation models

Covariance structure analysis is a statistical technique in which a theoretical model, or a covariance structure, is constructed, and the covariances predicted by the theoretical model are compared with those of the observed data. The adequacy of the model in reproducing the sample covariances is reflected by estimates of the parameters of the model and measures indicating the goodness of fit. Covariance structure analysis is frequently used for analyzing data obtained in nonexperimental or quasiexperimental research, but is seldom employed in experimental research. In this paper, the applicability of this technique in experimental research is discussed and illustrated by covariance structure analysis studies in which two models for word translation—the symmetrical model and the asymmetrical model—are described, refined, and contrasted.     

A Note on Justice,Care, and Immigration Policy

Should a “caring” immigration policy give special treatment to would-be immigrants who are near neighbors? It is argued that, while those on our borders requesting entry have some special claim, it should not drown out the claims of more distant applicants for citizenship.     

Feature analysis and the token test

In a picture-matching task pictures of objects had to be arranged into pairs by aphasic and nonaphasic patients and normal controls. Aphasic patients were also given the Token Test. Correlation between the rank order of error scores in both tests was highly significant in aphasic patients. The pictures were also given to a normal group for free matching. Overlapping of normal performance on free matching and aphasic performance on bound matching occurred. We hypothesized that aphasic impairment was due to a difficulty in calling up associations, difficulty in feature analysis, and in moving from one concept to another. These findings are discussed in the light of abilities needed for Token Test performance. The results indicate that the traditionally presumed fundamental difference between verbal and nonverbal cognitive tasks is rather unsatisfactory.     

Short- and long-term effects of marital disruption on children

The short- and long-term (5 years later) effects of parental marital disruption on the psychological adjustment of children were examined. A representative community sample of urban families (N = 1,034) in which 25-50% had experienced marital disruption constituted the sample. The effect of the presence and type of father figure in the home on children's adjustment, controlling for ethnic group and social class, was evaluated with respect to measures of psychological symptomatology (based on mother's report). Significant effects of the father figure variable on the dimensions measuring Noncompulsivity and Delinquency were found at both time periods. Children with natural fathers showed the least pathology on the Delinquency factor and those with surrogate fathers demonstrated the most disordered behavior on the Noncompulsivity factor. These findings complement previous research showing stability of antisocial behavior over time. Implications for preventive interventions and future research are discussed.