The objective definition of simple structure in linear factor analysis

Requirements for an objective definition of simple structure are investigated and a number of proposed objective criteria are evaluated. A distinction is drawn between exploratory factorial studies and confirmatory factorial studies, with the conclusion drawn that objective definition of simple structure depends on study design as well as on objective criteria. A proposed definition of simple structure is described in terms of linear constellations. This definition lacks only a statistical test to compare with possible chance results. A computational procedure is also described for searching for linear constellations. This procedure is very laborious and might best be accomplished on high-speed automatic computers. There is no guarantee that the procedure will find all linear constellations, but it probably would yield satisfactory results for well-designed studies.     

Control of selective echolalia via the instatement of a general alternative response

Treatment for echolalic responding has been limited to the training of a small number of correct responses and limited stimulus verbalizations by the experimenter, leaving the possibility that the introduction of novel stimuli could result in the reoccurrence of echolalia. In the present study an 11-year-old severely retarded male's echolalic responding to questions that he could not answer correctly was controlled by instating a general alternative response, “I don't know.” The subject continued to respond correctly to questions that he could answer. indicating that the general alternative response had been appropriately discriminated. A Baseline. Treatment. DRO. Treatment design indicated that the subject's echolalic responding, as well as the appropriate use of the general alternative response, was under experimental control. Generalization of the experimental results to the subject's regular day-care setting was accomplished by having the staff verbally punish all echolalic responses and then restate the question to the subject until a non-echolalic answer had been emitted. Implications of these findings and suggestions for combining previous treatment procedures for echolalia with the general alternative response procedure were offered.     

Reliability of the Halstead-Reitan Battery in individuals displaying acutely psychotic behavior

The purpose of the present study is to examine the test-retest reliability of the Halstead-Reitan Battery (HRB) in an acutely psychotic population. Ten acutely psychotic patients, initially tested upon admission to an inpatient unit of the Austin State Hospital, were selected for retesting on the basis of showing the most complete remission of psychotic symptoms of all patients tested over the 14-month period from June 1978 to August 1979. Only patients showing good remission were selected in order to maximize the potential for changes in test performance to occur and, thus, provide a conservative estimate of test-retest reliability. The average retest interval was 10.4 weeks (SD=6.67), with retest being completed just prior to discharge. Reliability was examined for each HRB subtest across subjects, as well as for each subject across subtest. While the patients generally showed an improved performance at retest, the reliability of the HRB was relatively high.     

A rule analysis of judgments of covariation between events

Several strategies are proposed as bases for judgments of covariation between events. Covariation problems were structured in such a way that patterns of correct and incorrect judgments would index the judgment rule being used by a given subject. In two experiments, 10th-grade or college subjects viewed a set of covariation problems, each of which consisted of a set of observations in which each of two events was defined as present or absent. Subjects were asked to identify the relationship between the events. Subjects’ response patterns suggested that the modal strategy was to compare frequency of confirming and disconfirming events in defining the relationship. Response accuracy was influenced by pretraining on the concept of covariation and by response format. Instructions to sort the observations did not influence judgment accuracy.     

Why classroom token economies fail

The reasons for clinical failures of classroom token economies are divided into three groups: (1) Problems associated with the token program itself, (2) Problems associated with the teacher, and (3) Problems associated with the specific population on which the classroom token economy is used. Each of these problem areas is discussed. Methods of anticipating problems before they occur are enumerated and ways of solving them should they occur are illustrated.     

Relations between multidimensional scaling and three-mode factor analysis

A combination is achieved of two lines of psychometric interest: a) multidimensional scaling and b) factor analysis. This is accomplished with the use of three-mode factor analysis of scalar product matrices, one for each subject. Two of the modes are the groups of objects scaled and the third mode is the sample of subjects. Results are an object space, a person space, and a system for changing weights given to dimensions and of angles between dimensions in the object space for individuals located at different places in the person space. The development is illustrated with data from an adjective similarity study.Supported in part by the Personnel and Training Branch of the Office of Naval Research under Contract Number 00014-67-A-0305-0003. A number of very helpful comments were made by an anonymous editorial reviewer forPsychometrika.During 1970–71 at the L. L. Thurstone Psychometric Laboratory, University of North Carolina.     

Differentiating the N3 and N4 electrophysiological semantic incongruity effects

An event-related potential termed the N4 has been widely studied due to its sensitivity to semantic incongruity. A recent report (Nobre & McCarthy, 1994) indicates there is also an N3 component that is sensitive to semantic incongruity. To differentiate these two components, an existing data set with 65 electrode sites, 78 subjects, and 120 sentences was examined. Instead of the usual procedure of averaging over the stimuli within distinct categories for each subject, a new approach--averaging over subjects--was employed. In this item average approach, 120 averages (one per sentence) were produced. Correlational analyses indicate that the N3 is equally sensitive to cloze probability and sentential constraint. The N4, by contrast, is more sensitive to sentential constraint and less to cloze probability; it is also correlated with familiarity. We interpret these results as evidence that the N3 is more responsive to semantic fit whereas the N4 is more responsive to semantic expectancy.