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The authors hypothesized that schizophrenic communication disturbances reflect specific cognitive deficits in the areas of working memory and attention. They examined the cognitive correlates of communication disturbances, as measured by linguistic reference performance, in schizophrenic (n = 48), bipolar (n = 24), and nonpsychiatric control (n = 23) individuals. Reference performance ratings in the schizophrenic patients were associated with scores on tests of working memory and attention and were not related to performance on concept formation or verbal fluency tests. In contrast, in the bipolar and nonpsychiatric individuals, reference performance was associated with concept formation and verbal fluency test scores but was not related to performance on tests of working memory. Implications with respect to the processes underlying schizophrenic communication disturbances are discussed.

Most community college graduates do not continue on for study in 4-year colleges and universities. Fewer than 20% do so within the first few years after receiving their associate's degrees. Concerns have been expressed about the extent to which older students (e.g., students who received their degrees at age 25 and above) persist (go on) to 4-year colleges and universities and about the correlates of persistence for this group. The purpose of this study was to examine the relationships between a selected number of academic, social, and personal variables in the context of predicting persistence to a 4-year public university among older graduates of a New England state’s public 2-year institutions. Data were collected in 1988 and 1989 from a random sample of 3,762 older associate's degree students from the 12 community colleges in Connecticut. These data were then subjected to a two-group, single-function discriminant function analysis to determine the predictive power of the dependent measures used in the study. The results indicated that the higher the perceptions of social and institutional support in community colleges and the higher the age of the graduates, the more apt they were to persist to a 4-year institution. Further analysis, however, revealed that the average persister was 38 years old, whereas the average attritor was 34 years old, suggesting the need for further research among 2-year college populations among the over-30 age group as well as replication of the study in states with both similar and dissimilar demographic shifts in college populations. © 1996 Taylor and Francis Group, LLC.

A discrete-trials adjusting-delay procedure was used to investigate the conditions under which pigeons might show a preference for partial reinforcement over 100% reinforcement, an effect reported in a number of previous experiments. A peck on a red key always led to a delay with red houselights and then food. In each condition, the duration of the red-houselight delay was adjusted to estimate an indifference point. In 100% reinforcement conditions, a peck on a green key always led to a delay with green houselights and then food. In partial-reinforcement conditions, a peck on the green key led either to the green houselights and food or to white houselights and no food. In some phases of the experiment, statistically significant preference for partial reinforcement over 100% reinforcement was found, but this effect was observed in only about half of the pigeons. The effect was largely eliminated when variability in the delay stimulus colors was equated for 50% reinforcement conditions and 100% reinforcement conditions. Idiosyncratic preferences for certain colors or for stimulus variability may be at least partially responsible for the effect.

The current study examined the nature and style of mother-adolescent conversations, how these conversations differ by subject matter and dyadic and individual differences. Thirty-one mother-adolescent dyads (17 boys, 14 girls) with a child between the ages of 11 and 14 had a nonstructured conversation and conversations about conflict and sexuality They also completed questionnaires on beliefs about acquired immunodeficiency syndrome (AIDS). Conversations were measured for turn taking, total number of words, and conversational dominance, as well as nonverbal measures of affiliation, shame, and contempt Conversations about sexuality involved less turn taking, fewer words, and more mother dominance than nonstructured conversations. Conversations about conflicts involved less turn taking but more words than nonstructured conversations Some gender and age differences were found. Move interactive conflict conversations contained higher levels of affiliation, and lower levels of child shame than conversations with fewer turns or higher mother dominance. In addition, children in move interactive dyads possessed a larger percentage of their mother's AIDS knowledge, and worried about AIDS a moderate amount.

Two experiments investigated how individuals use explicit memory cues that designate different probabilities of test. As in typical directed forgetting studies, subjects received words explicitly cued as having either a 0% or a 100% chance of being on a subsequent memory test (i.e. forget and remember cues, respectively). In addition, some words were explicitly cued as having the potential to be either forgotten or remembered (i.e. a 50% cue). Recall of 50% words was between that of 0% and 100% words. In addition, the presence of 50% words lowered recall of the 100% words compared to that of a control group that did not receive the 50% words, but received the same number of 100% words. A think-aloud task indicated that these results were due to the 50% words being treated like either 100% or 0% words at encoding. The results are discussed in terms of the effect of different probabilities of test on the strategic processing and representation of information.

Pigeons' responses on two keys were recorded before and after the percentage of reinforcers delivered by each key was changed. In each condition of Experiment 1, the reinforcement percentage for one key was 50% for several sessions, then either 70% or 90% for one, two, or three sessions, and then 50% for another few sessions. At the start of the second and third sessions after a change in reinforcement percentages, choice percentages often exhibited spontaneous recovery-a reversion to the response percentages of earlier sessions. The spontaneous recovery consisted of a shift toward a more extreme response percentage in some cases and toward a less extreme response percentage in other cases, depending on what reinforcement percentages were previously in effect. In Experiment 2, some conditions included a 3-day rest period before a change in reinforcement percentages, and other conditions included no such rest days. Slightly less spontaneous recovery was observed in conditions with the rest periods, suggesting that the influence of prior sessions diminished with the passage of time. The results are consistent with the view that choice behavior at the start of a new session is based on a weighted average of the events of the past several sessions.

STIR, Success Through Individual Recreation is examined to determine the benefits of individualized recreational activities geared towards the lower functioning...

In three experiments, pigeons chose between alternatives that required the completion of a small ratio schedule early in the trial or a larger ratio schedule later in the trial. Completion of the ratio requirement did not lead to an immediate reinforcer, but simply allowed the events of the trial to continue. In Experiment 1, the ratio requirements interrupted periods in which food was delivered on a variable-time schedule. In Experiments 2 and 3, each ratio requirement was preceded and followed by a delay, and only one reinforcer was delivered, at the end of each trial. Two of the experiments used an adjusting-ratio procedure in which the ratio requirement was increased and decreased over trials so as to estimate an indifference point-a ratio size at which the two alternatives were chosen about equally often. These experiments found clear evidence for `'procrastination”-the choice of a larger but more delayed response requirement. In some cases, subjects chose the more delayed ratio schedule even when it was larger than the more immediate alternative by a factor of four or more. The results suggest that as the delay to the start of a ratio requirement is increased, it has progressively less effect on choice behavior, in much the same way that delaying a positive reinforcer reduces it effect on choice.

Two experiments investigated how college students answered direction-giving questions when a confederate asked for directions to a destination on a university campus. The experiments applied the QUEST model (Graesser and Franklin, 1990) to direction giving, emphasizing the pragmatic component of the model that focuses on establishing common ground and dealing with the questioner's goals. The two experiments had different articulations of the direction-giving question (i.e.'How do you get to destination X?' versus `Where is destination X?'), and a different destination. The answers generated by subjects supported both aspects of the pragmatic component.

The author agrees with James Moor that computer technology, because it is 'logically malleable', is bringing about a genuine social revolution. Moor compares the computer revolution to the 'industrial revolution' of the late 18th and the 19th centuries; but it is argued here that a better comparison is with the 'printing press revolution' that occurred two centuries before that. Just as the major ethical theories of Bentham and Kant were developed in response to the printing press revolution, so a new ethical theory is likely to emerge from computer ethics in response to the computer revolution. The newly emerging field of information ethics, therefore, is much more important than even its founders and advocates believe.

Objective: To review family-based treatment research. A growing body of research and several meta-analytic reviews demonstrate that family-based treatments are effective for a variety of child and adolescent disorders. In addition, an emerging tradition of family-based process research has begun to identify important ingredients of effective family psychotherapy. This article reviews these advances and their implications for future research. Method: Selected studies on the treatment of schizophrenia, depression, anxiety, eating disorders, attention deficit, conduct disorder, and substance abuse are reviewed, as well as several process research and meta-analytic studies. Results: Family-based therapies have been shown to be effective for treating schizophrenia, conduct disorder, and substance abuse. Some data support their effectiveness in the treatment of eating disorders. Few studies have targeted internalizing disorders. A process research tradition is emerging, but it is in need of methodological advances, Meta-analytic studies suggest that family-based therapies are as effective as other models. Conclusions: More well-designed studies with diverse populations are needed to assess accurately the effectiveness of this increasingly popular treatment approach.

The purpose df this paper is to examine factors that affect the calibration of judgments by systematically comparing experts' judgments to novices' when solving a complex, real-world problem that varies in its initial characteristics. Calibration in this context refers to the proportion of times decision makers provide a range about their best estimates that includes the actual outcome. We found that experts specify a narrower range and provide more accurate best estimates than novices. But their tighter ranges are not justified by their greater accuracy: they are less likely to encompass the actual outcome than are novices. However, this effect is attenuated when solving more complex problems. Novices apparently underestimate the complexity of difficult problems, hence the accuracy of their best estimates decreases as does the width of their ranges, resulting in worse calibration. The performance of experts was not significantly different across problem solving conditions. Both groups provided asymmetrical ranges about their best estimates, which suggests they account for the effect of subproblem dependencies. (C) 1996 Academic Press, Inc.

Basic skills in reading and spelling and supporting metalinguistic abilities were assessed in ninth and tenth grade students in two school settings. Students attending a private high school for the learning disabled comprised one group and the other comprised low to middle range students from a public high school. Both the LD students and the regular high school students displayed deficiencies in spelling and in decoding, a factor in reading difficulty that is commonly supposed to dwindle in importance after the elementary school years. Treating the overlapping groups as a single sample, multiple regression analysis was used to investigate the contribution of nonword decoding skill and phonological and morphological awareness to spelling ability. The analysis revealed that decoding was the major component, predicting about half of the variance in spelling. The effect of phonological awareness was largely hidden by its high correlation with decoding, but was a significant predictor of spelling in its own right. Morphological awareness predicted spelling skill when the words to be spelled were morphologically complex. An additional study showed that differences in decoding and spelling ability were associated with differences in comprehension after controlling for reading experience and vocabulary. Even among experienced readers individual differences in comprehension of text reflect efficiency of phonological processing at the word level.

A methodology is developed for combining mean value forecasts using not only all the important statistics related to the past performance and the dependence of the individual forecasts, but also a rank ordering of the individual forecasts representing the belief of a decision maker about the future performance of the forecasts. The maximum likelihood combination of the forecasts turns out to be a weighted linear combination of the individual forecasts, where the weights are a function of the rank order of the forecasts, correlation coefficients between the forecasts, and relative entropy information measures between the individual forecasts and the actual values. These weights are assessed once in the most general case and once in a special case where the forecasts are normally distributed. The sensitivity of the weights is also investigated. A sample application of this method for predicting U.S. hog prices is also presented.

This paper presents a methodology for producing a probability forecast of a turning point in U.S. economy using Composite Leading Indicators. This methodology is based on classical statistical decision theory and uses information-theoretic measurement to produce a probability. The methodology is flexible using as many historical data points as desired. This methodology is applied to producing probability forecasts of a downturn in U.S. economy in the 1970-1990 period. Four probability forecasts are produced using different amounts of information. The performance of these forecasts is evaluated using the actual downturn points and the scores measuring accuracy, calibration, and resolution. An indirect comparison of these forecasts with Diebold and Rudebusch's sequential probability recursion is also presented. It is shown that the performances of our best two models are statistically different from the performance of the three-consecutive-month decline model and are the same as the one for the best probit model. The probit model, however, is more conservative in its predictions than our two models.