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851.
Stimulus effects on concurrent performance in transition   总被引:2,自引:2,他引:0       下载免费PDF全文
Six experimentally naive pigeons were exposed to concurrent variable-interval variable-interval schedules in a three-key procedure in which food reinforcement followed pecks on the side keys and pecks on the center key served as changeover responses. In Phase 1, 3 birds were exposed to 20 combinations of five variable-interval values, with each variable-interval value consistently associated with a different color on the side keys. Another 3 pigeons were exposed to the same 20 conditions, but with a more standard procedure that used a nondifferential discriminative stimulus on the two side keys throughout all conditions. In Phase 2, the differential and nondifferential stimulus conditions were reversed for each pigeon. Each condition lasted for one 5-hr session and one subsequent 1-hr session. In the last 14 conditions of each phase, the presence of differential discriminative stimuli decreased the time necessary for differential responding to develop and increased the sensitivity of behavior to reinforcement distribution in the 1st hr of training; during the last hours of training in each condition, however, the effects of the differential discriminative stimuli could not be distinguished from the effects of reinforcement distribution per se. These results show the importance of studying transitions in behavior as well as final performance. They may also be relevant to discrepancies in the results of previous experiments that have used nonhuman and human subjects.  相似文献   
852.
In two experiments, key pecking of pigeons was maintained by a variable-interval 180-s schedule of food presentation. Conjointly, a second schedule delivered response-dependent electric shock. In the first experiment, shocks were presented according to either a variable-interval or a nondifferential interval-percentile schedule. The variable-interval shock schedule differentially delivered shocks following long interresponse times. Although the nondifferential shock schedules delivered shocks less differentially with respect to interresponse times, the two shock schedules equally reduced the relative frequency of long interresponse times. The second experiment differentially shocked long or short interresponse times in different conditions, with resulting decreases in the relative frequency of the targeted interresponse times. These experiments highlight the importance of selecting the appropriate level of analysis for the interaction of behavior and environment. Orderly relations present at one level of analysis (e.g., interresponse times) may not be revealed at other levels of analysis (e.g., overall response rate).  相似文献   
853.
Inelastic supply: An economic approach to simple interval schedules   总被引:1,自引:1,他引:0       下载免费PDF全文
Economic theory predicts an inverse relationship between the quantity of a commodity supplied to the marketplace and the equilibrium market price of that commodity. This prediction was tested in three experiments. Pigeons responded on simple variable-interval schedules, and quantity of reinforcement supplied was varied in a different way in each experiment. In Experiment 1, quantity supplied was varied by manipulating reinforcement rate while keeping session length constant. In Experiment 2, quantity supplied was varied by manipulating reinforcement rate while keeping reinforcers per session constant. In Experiment 3, quantity supplied was varied by manipulating reinforcer magnitude while keeping number of reinforcers constant. As predicted by economic theory, the obtained behavioral cost (responses per reinforcer) increased as supply decreased. The results could not be explained by simple artifacts such as satiation and time available to respond. In addition, the function relating response rate to reinforcement rate was bitonic in 7 of 9 animals in Experiments 1 and 2, which supports economic and regulatory theories over more traditional reinforcement theories.  相似文献   
854.
Six pigeons responded on two concurrently available keys that defined patches with the following characteristics. Reinforcer stores repleted on a patch as a linear function of time when the bird had last responded to the other patch, or else did not replete. Repletion schedules thus timed only when the bird was absent from the patch. Reinforcer stores on a patch could be depleted and reinforcers obtained, again as a linear function of time, when the bird responded on a key. Depletion schedules thus timed only when the birds were present at a patch. Experiment 1 investigated changing relative depletion rates when repletion rates were constant and equal (Part 1) and changing relative repletion rates when the depletion rates were constant and equal (Part 2). Response- and time-allocation ratios conformed to a generalized matching relation with obtained reinforcer ratios, and there appeared to be no control by the size of the reinforcer stores. In Experiment 2, absolute depletion rates were varied with a pair of unequal repletion rates (Part 3), and absolute repletion rates were varied with a pair of unequal depletion rates (Part 4). Dwell times in the patches were not affected by either variation. Melioration theory predicted the results of Experiment 1 quite closely but erroneously predicted changing dwell times in Experiment 2. Molar maximization theory did not accurately predict the results of either experiment.  相似文献   
855.
In a court clinic sample of 107 child sexual and nonsexual offenders, Minnesota Multiphasic Personality Inventory (MMPI) profiles did not differ as a function of arrests for sexual versus nonsexual offending. However, a three-group cluster-analytic solution was generated. Two of these clusters replicated those derived by Hall, Graham, and Shepherd (1991). The first cluster was unelevated, with Scales 4 and 9 as high points. The second cluster had MMPI Scales 4, 8, 2, and 7 as the highest scales. The third cluster was even more elevated than the other two clusters, characterized by extreme elevations on MMPI Scales F, 2, 4, 6, 7, and 8. The somewhat different results of this study versus previous studies (e.g., Hall et al., 1991) may be a function of the different populations sampled. The results provide evidence of within-group heterogeneity among sexual and nonsexual offenders that may be as important as between-group differences.  相似文献   
856.
We evaluated the efficacy of the Addiction Potential Scale (APS) and the Addiction Acknowledgement Scale (AAS), two new scales designed to assess substance abuse problems with the Minnesota Multiphasic Personality Inventory-2 (MMPI-2), in samples from settings different from those used in their development. Results replicate earlier findings that both scales discriminate between psychiatric and substance abuse samples and do so more effectively than other substance abuse scales designed for use with the MMPI and carried over to the MMPI-2. Results also suggest that APS may be more resistant than AAS to response distortion.  相似文献   
857.
Nomothetic and idiographic content analytic approaches to the Rorschach are used in complementary fashion to explore the psychotic personality structure and primitive interpersonal models in a 37-year-old biologically normal male, who was a gynemimetic, that is, a transvestite who aspired to have the genetalia of a woman. The Rorschach was riddled with psychotic verbalizations and imagery suggesting inadequate differentiation from the original symbiosis, inadequate symbiosis anxiety, and significant separation anxiety--a constellation culminating in the transsexual fantasy of fusion with the mother.  相似文献   
858.
The Rorschach Inkblot Test has been the source of long-standing controversies as to its nature and its psychometric properties. Consistent with behavioral science research in general, the concept of statistical power has been entirely ignored by Rorschach researchers. The concept of power is introduced and discussed, and a power survey of the Rorschach literature published between 1975 and 1991 in the Journal of Personality Assessment, Journal of Consulting and Clinical Psychology, Journal of Abnormal Psychology, Journal of Clinical Psychology, Journal of Personality, Psychological Bulletin, American Journal of Psychiatry, and Journal of Personality and Social Psychology was undertaken. Power was calculated for 2,300 statistical tests in 158 journal articles. Power to detect small, medium, and large effect sizes was .13, .56, and .85, respectively. Similar to the findings in other power surveys conducted on behavioral science research, we concluded that Rorschach research is underpowered to detect the differences under investigation. This undoubtedly contributes to the inconsistency of research findings which has been a source of controversy and criticism over the decades. It appears that research conducted according to the Comprehensive System for the Rorschach is more powerful. Recommendations are offered for improving power and strengthening the design sensitivity of Rorschach research, including increasing sample sizes, use of parametric statistics, reduction of error variance, more accurate reporting of findings, and editorial policies reflecting concern about the magnitude of relationships beyond an exclusive focus on levels of statistical significance.  相似文献   
859.
The author compares and contrasts insight-oriented psychotherapy, supportive psychotherapy, and spiritual direction in relation to goals and methods; management of resistance, transference, and countertransference; and selection criteria. The enhancement of spiritual formation through insight-oriented psychotherapy and supportive psychotherapy is also discussed.  相似文献   
860.
There is usually a long period of time between infection with the AIDS virus and manifestation of symptoms. Asymptomatic patients often would benefit from elective surgery for diseases such as arthritis which are unrelated to their infection. The surgeons' decisions to accept the risks to themselves, their spouses, and their operating teams in order to relieve pain and suffering appear to be based upon two covenants; one concerns their role within the doctor-patient relationship, and the other concerns their relationship to what they see as the ultimate meaning in life.  相似文献   
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