Psychometric latent response models

In this paper, some psychometric models will be presented that belong to the larger class oflatent response models (LRMs). First, LRMs are introduced by means of an application in the field ofcomponential item response theory (Embretson, 1980, 1984). Second, a general definition of LRMs (not specific for the psychometric subclass) is given. Third, some more psychometric LRMs, and examples of how they can be applied, are presented. Fourth, a method for obtaining maximum likelihood (ML) and some maximum a posteriori (MAP) estimates of the parameters of LRMs is presented. This method is then applied to theconjunctive Rasch model. Fifth and last, an application of the conjunctive Rasch model is presented. This model was applied to responses to typical verbal ability items (open synonym items).This paper presents theoretical and empirical results of a research project supported by the Research Council [Onderzoeksraad] of the University of Leuven (grant number 89-9) to Paul De Boeck and Luc Delbeke.     

The relationship between pronunciation and listening discrimination when Japanese natives are learning English

Two Japanese students were taught to pronounce and discriminate English words that contain unfamiliar phonemic contrasts (e.g., rock and lock). Teaching pronunciation was found to be easier than teaching listening discrimination. Teaching listening discrimination resulted in collateral improvement in pronunciation and, to a lesser extent, vice versa.     

Bias in self-evaluation: Signal probability effects

Two experiments examined apparent signal probability effects in simple verbal self-reports. After each trial of a delayed matching-to-sample task, young adults pressed either a “yes” or a “no” button to answer a computer-presented query about whether the most recent choice met a point contingency requiring both speed and accuracy. A successful matching-to-sample choice served as the “signal” in a signal-detection analysis of self-reports. Difficulty of matching to sample, and thus signal probability, was manipulated via the number of nonmatching sample and comparison stimuli. In Experiment 1, subjects exhibited a bias (log b) for reporting matching-to-sample success when success was frequent, and no bias or a bias for reporting failure when success was infrequent. Contingencies involving equal conditional probabilities of point consequences for “I succeeded” and “I failed” reports had no systematic effect on this pattern. Experiment 2 found signal probability effects to be evident regardless of whether referent-response difficulty was manipulated in different conditions or within sessions. These findings indicate that apparent signal probability effects in self-report bias that were observed in previous studies probably were not an artifact of contingencies intended to improve self-report accuracy or of the means of manipulating signal probability. The findings support an analogy between simple self-reports and psychophysical judgments and bolster the conclusion of Critchfield (1993) that signal probability effects can influence simple self-reports much as they do reports about external stimuli in psychophysical experiments.     

Characteristic patterns of verbal memory function in patients with Huntington's disease

Various aspects of verbal memory in patients with Huntington's disease (HD) were studied using the California Verbal Learning Test (CVLT). We tested if the level and interplay between 5 parameters of different memory mechanisms and processes were sufficiently specific to allow acceptable discrimination between patients with HD, patients with Parkinson's disease (PD), and patients without known CNS disease or injury. The HD-patients were characterized by a deficit in acquisition, elevated rates of recall errors and increased use of a passive learning strategy. Preserved aspects were shown in retention over time, interference effects and recognition relative to recall. Employing multivariate classification and validation techniques, the 5 CVLT-features demonstrated good separability between the HD-patients and the control patients. Qualitative similarities between subgroups were suggested, but more disease-specific data seemed necessary in further studies. A number of findings suggested a defect in the active organization of items to be encoded and recalled in HD. Similar findings in the PD-group might indicate that this trait is common in several types of 'subcortical dementia'.     

Concurrent activities and instructed human fixed-interval performance.

Two experiments explored the effects of two types of concurrent activity on human fixed-interval performance. Eight adult subjects were given access to either reading material or a working television set across three fixed-interval values (60 s, 300 s, and 600 s). During Experiment 1, 2 subjects produced "scalloped" patterns and reported no verbal regulation (e.g., counting) in the presence of the reading material, but shifted to low-rate patterns and reported verbal regulation when the reading material was withdrawn. The 2 other subjects in Experiment 1 produced consistent low-rate performances and reported verbal regulation during access to reading material. However, when these subjects were given access to a working television set, they produced scalloped patterns and reported no verbal regulation. During Experiment 2, 4 experimentally naive subjects showed consistent scalloped patterning and no verbal regulation across fixed-interval values when they were allowed to watch television. When access to the television was denied, subjects reliably reported verbal regulation, and low-rate patterns emerged. These behavioral effects focus our attention on the contingencies that control human performance on fixed-interval schedules.     

DEVELOPMENT OF SPONTANEOUS MANDING IN LANGUAGE DEFICIENT CHILDREN

Six institutionalized children, aged 7–11, with little or no spontaneous vocal manding, were trained to request food items under appropriate natural conditions when snacks were presented. “I want a” was appropriate when an adult presented food in the playroom. “Out” was appropriate when the items were displayed in the hallway, across a half-door barrier from the child. A sequence of steps was trained, through increasingly naturalistic setting and cuing conditions. The two mands were trained in sequence, not concurrently. To encourage “spontaneous” productions, no vocal cuing was provided by the adult. After criterion performance in each step, several probe sessions were conducted for various cuing conditions, adults, and settings. Probes after imitation training showed no spontaneous manding. Thus, failure of manding was not due to production difficulties. In probes after training for “approximately” natural cues, most children showed little transfer to the natural cues. This implies that training for the specific appropriate cues may often be required. However, good transfer generally occurred across persons, and from training room to playroom. Probes also showed that most children did not use one of the trained mands in the stimulus conditions that were appropriate for the other mand. Thus, adding a second mand did not generally disrupt use of the first. However, significant disruption occurred for two children. Finally, at the end of training, extinction training was given for one mand in one setting. Performance of the other mand was litle affected. In sum, the appropriate form of a mand depends on specific stimulus and setting characteristics, and these characteristics must be considered in training.     

OVERCORRECTION: GENERALIZATION AND MAINTENANCE1

The present study examined the effects of one component of overcorrection—verbal reprimands—and compared them with the effects of the entire overcorrection procedure. Generalization and maintenance of effects were also evaluated. A combined reversal and multiple-baseline experimental design was used to evaluate the effect of the various contingencies on the inappropriate searching behavior of a severely and profoundly mentally retarded adult living in a group home. Searching was defined as carefully and thoroughly touching floors, sofas, cabinets, etc. Data were collected by group-home personnel during three separate observation periods each day of the 115-day study: before breakfast, after breakfast, and after dinner. Observers also served as experimenters. Following an initial baseline phase, verbal reprimands followed searching behavior during two daily experimental periods in multiple-baseline fashion. An immediate reduction of searching during experimental periods occurred with the onset of verbal reprimands. No reduction was observed in the third daily observation period, the control session. After a second baseline phase, during which searching behavior was not shown to return to the original baseline levels, overcorrection procedures (washing hands) were instituted. Overcorrection virtually eliminated inappropriate searching during both daily experimental periods. Further, the effects generalized to the daily control session. In a final experimental phase, decreased searching behavior was maintained with verbal reprimands alone.     

Natural rates of teacher approval and disapproval in grade-7 classrooms

The natural rates of teacher verbal approval and disapproval in ten grade-seven classrooms were determined and compared with those described by White (1975). Although there were differences in the observation techniques used and the behavioral, cultural, and ethnic groups sampled, the results were similar. The majority of the teachers displayed individual rates of disapproval that were higher than their individual approval rates. The correlations between levels of on-task behavior and approval and disapproval rates were low. The issues raised by these findings are discussed in terms of directions for further research.     

Some thoughts on correspondence between saying and doing

Recent research on verbal-nonverbal correspondence is evaluated, and conceptual, methodological, and applied issues regarding correspondence are addressed. Directions for research concerning the correspondence training procedure and extended applications are suggested.     

AN INVESTIGATION OF THE EFFECTS OF TOKEN REINFORCEMENT ON DIVERGENT VERBAL RESPONDING1

The effect of token reinforcement on three classes of divergent verbal responding to verbal stimulus items from three measures of the Wallach-Kogan Creativity test was examined. The subjects consisted of two “gifted”, two “average”, and two “learning disabled” children from a public-school setting. The design utilized both an intra-subject and inter-subject multiple-baseline design with a reversal design added. Tokens were dispensed contingent upon the number of appropriate verbal responses to each stimulus item, i.e., a continuous schedule of reinforcement was used—one token per appropriate response. Interobserver agreement on “appropiateness” was 993%. The tokens could be used to “purchase” items listed in a “menu” format (e.g., ball and jacks—100 tokens). Consistently large effects of token reinforcement were observed, without generalization of effect across the three classes of behaviors, or conditions. These results support the works of Goetz and Baer (Journal of Applied Behavior Analysis, 1973, 6 , 209–217), Goetz and Salmonson (Behavior Analysis and Education, G. Semb, (Ed.), University of Kansas, 1972, 53–61), and Maloney and Hopkins (Journal of Applied Behavior Analysis, 1973, 6 , 425–434). Implications lie in continued experimental analysis of behavior approach to the concept called “creativity”. Additionally, implications are made in classroom application of assessing and intervening in the area of divergent responding for children with deficits in those areas.