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21.
Using recall of clinical protocols as a measure of expertise in medicine has yielded disappointingly small effects. Experiments using recall of clinical laboratory data are presented to provide an explanation. In one experiment, subjects either deliberately memorized or first diagnosed and then were incidentally asked for memory. With incidental instructions, experts recalled over twice as much data as did students, but with memorization instructions, student performance approximated that of experts. Experts also showed a large advantage over students in incidental recall of data that were not relevant to the problem solution. These results suggest that expert processing in this "discrete, independent inputs" domain requires effortful analysis with minimal reliance on default values, rather than relatively effortless pattern perception reported in highly visual areas of expertise. For this area, intentional memory is a misleading measure of expertise. However, incidental memory is a valuable measure of processing during diagnosis.  相似文献   
22.
A survey of 942 university staff employees shows that performance and cost of living are preferred over seniority as criteria upon which to base pay increases. Multiple regression analysis reveals that preferences for performance-based pay increases are most strongly related to perceptions that merit pay does not decrease co-worker cooperation, perceptions that performance differences exist among co-workers, employment in white collar jobs, and never having belonged to a union. Preferences for seniority-based and cost of living-based pay increases are most strongly related to the perceived need for a union, perceptions that merit pay reduces cooperation, education level, and gender. In addition, preferences for seniority-based pay increases are related to years of service.An earlier version of this paper was presented at the 1989 meetings of the Midwest Academy of Management.  相似文献   
23.
The "psychosomatic family" model: an empirical and theoretical analysis   总被引:3,自引:0,他引:3  
Evolution of the Family Systems Paradigm has been constrained by the dichotomy between theory building and empirical research. This article integrates these two domains by presenting a theoretical analysis of the "psychosomatic family" model as it informs and is informed by an empirical research project. Forty families of children with Crohn's disease (CD), ulcerative colitis (UC), and functional recurrent abdominal pain syndrome (RAP) were rated during standard, videotaped family interaction tasks, lunch, and interview. Laboratory scores of disease activity were associated with triangulation, marital dysfunction, and total "psychosomatic family" scores. Disease activity was not significantly correlated with enmeshment, overprotection, rigidity, conflict avoidance, or poor conflict resolution. Thus, the marital/triangulation and enmeshment/overprotection/conflict clusters may be subcomplexes of the "psychosomatic family" complex. CD, UC, and RAP groups differed in the relations among particular family patterns and disease activity. A heuristic family-psycho-somatic model is presented to facilitate future research.  相似文献   
24.
25.
We investigated the utilization and efficacy of distraction in reducing the anxious and disruptive behavior of 4 children undergoing dental treatment. During the distraction procedure, the children were shown a poster and told a story about it during dental treatment. They earned a prize if they attended to the poster and story and could correctly answer questions about them following each intervention visit. The children's disruptive behavior was assessed via direct observation, and results were analyzed within a multiple baseline design. The children exhibited high levels of anxious and disruptive behavior across baseline visits, regardless of the length of time in treatment or number of visits. Anxious and disruptive behavior decreased upon introduction of the intervention for all children. This was accompanied by the children meeting the criterion for correct answers on the distraction quiz. However, 2 of the children demonstrated an increase in their anxious and disruptive behavior across intervention visits. Results are discussed in terms of the need to evaluate treatment strategies that promote maintenance as well as initial changes.  相似文献   
26.
Carroll JB  Andrusko D 《America》1985,152(21):450-453
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27.
Three-way metric unfolding via alternating weighted least squares   总被引:6,自引:3,他引:3  
Three-way unfolding was developed by DeSarbo (1978) and reported in DeSarbo and Carroll (1980, 1981) as a new model to accommodate the analysis of two-mode three-way data (e.g., nonsymmetric proximities for stimulus objects collected over time) and three-mode, three-way data (e.g., subjects rendering preference judgments for various stimuli in different usage occasions or situations). This paper presents a revised objective function and new algorithm which attempt to prevent the common type of degenerate solutions encountered in typical unfolding analysis. We begin with an introduction of the problem and a review of three-way unfolding. The three-way unfolding model, weighted objective function, and new algorithm are presented. Monte Carlo work via a fractional factorial experimental design is described investigating the effect of several data and model factors on overall algorithm performance. Finally, three applications of the methodology are reported illustrating the flexibility and robustness of the procedure.We wish to thank the editor and reviewers for their insightful comments.  相似文献   
28.
Youth suicide     
B P Allen 《Adolescence》1987,22(86):271-290
The literature on youth suicide (ages 15-24) is surveyed for the period 1980-1985. Emphasis is placed on general determinants of suicide, predictors in the form of psychological tests, precipitating events (immediate causes), and signs--clues that may signify impending attempts at self-destruction. Suggestions for prevention, and limitations of research on suicide are offered.  相似文献   
29.
A reinforced practice procedure was used to facilitate cooperative behavior in five children, aged 3 to 6 years, during dental treatment. In a multiple baseline design across subjects, the children were rewarded with escape, inexpensive stickers, and praise for cooperative behavior in the presence of the sights, sounds, and some sensations of the dental instruments prior to actual dental treatment. Direct observations of disruptive behavior via a 15-s interval recording system indicated baseline levels as high as 90% were reduced to less than 15% by the final treatment visit. In addition, the procedure was effective in reducing overall heart rate and blood pressure reactivity to dental treatment. All children were rated by the involved dental professionals as more cooperative and relaxed following exposure to reinforced practice.  相似文献   
30.
Two experiments addressed the effects of food satiation and deprivation on oral self-administration of two concurrently available phencyclidine concentrations. In the first experiment, 8 rhesus monkeys self-administered either of two concentrations of phencyclidine ("PCP, angel dust") and water under concurrent fixed-ratio 16 schedules. One concentration was always held constant (0.25 mg/mL) while a series of other phencyclidine concentrations, ranging from 0 (water) to 1.0 mg/mL, was presented in a nonsystematic order. Initially the monkeys were tested while food satiated, and the procedure was then repeated during food deprivation. The monkeys usually selected the higher concentration within the first few minutes of the session, indicating that taste and/or other immediate postingestional effects were important factors. Contrary to a number of previous reports, there were no consistent differences across subjects in the mean number of liquid deliveries or mean drug intake (mg/kg) during food satiation and deprivation. However, for all monkeys the within-session time course of responding during food satiation consistently differed from that during deprivation. A second experiment assessed whether the failure to find consistent differences in drug intake during food satiation and deprivation had been due to the history of concurrent access to different phencyclidine concentrations or to the extended experience with phencyclidine under food-satiation conditions. Six additional monkeys (Group 2) were exposed to the phencyclidine self-administration procedure (during food satiation and deprivation) for the same length of time as the monkeys in Experiment 1 (Group 1), except they received only concurrent access to phencyclidine (0.25 mg/mL) and water. Both groups then received concurrent access to phencyclidine and water during five repeated cycles of food deprivation and satiation. There were also marked individual differences in Group 2: During food satiation, 2 of the monkeys' responding increased, 1 showed no change, and 3 decreased. Examination of a number of historical variables indicated that the greater the percentage of total sessions spent during food satiation with phencyclidine available (before these experiments began), the greater the amounts of phencyclidine consumed during food satiation and the smaller the differences in phencyclidine intake when the two feeding conditions were compared.  相似文献   
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