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991.
Behavioral momentum theory relates resistance to change of responding in a multiple-schedule component to the total reinforcement obtained in that component, regardless of how the reinforcers are produced. Four pigeons responded in a series of multiple-schedule conditions in which a variable-interval 40-s schedule arranged reinforcers for pecking in one component and a variable-interval 360-s schedule arranged them in the other. In addition, responses on a second key were reinforced according to variable-interval schedules that were equal in the two components. In different parts of the experiment, responding was disrupted by changing the rate of reinforcement on the second key or by delivering response-independent food during a blackout separating the two components. Consistent with momentum theory, responding on the first key in Part 1 changed more in the component with the lower reinforcement total when it was disrupted by changes in the rate of reinforcement on the second key. However, responding on the second key changed more in the component with the higher reinforcement total. In Parts 2 and 3, responding was disrupted with free food presented during intercomponent blackouts, with extinction (Part 2) or variable-interval 80-s reinforcement (Part 3) arranged on the second key. Here, resistance to change was greater for the component with greater overall reinforcement. Failures of momentum theory to predict short-term differences in resistance to change occurred with disruptors that caused greater change between steady states for the richer component. Consistency of effects across disruptors may yet be found if short-term effects of disruptors are assessed relative to the extent of change observed after prolonged exposure.  相似文献   
992.
What Do We Know When We Know a Person?   总被引:12,自引:1,他引:11  
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993.
Few studies have examined the correlational and structural relationships between measures of hostility that may predict coronary heart disease. Using data from a population-based study (N= 2,682), we examined the factor structure among the five subscales from Siegel's (1986) Multi-dimensional Anger Inventory, the three subscales from Spielberger et al.'s (1985) anger expression scales, a Cook-Medley (Cook & Madley, 1954) hostility subscale that measures cynicism, and items measuring hostility from four scales that assess Type A behavior. Eight separate factors were identified: hostile anger expression, perceived control over the expression of one's anger, frequency of anger, ease of anger provocation, brooding, hostile outlook, cynicism, and sullenness. These results suggest that the structure of hostility measures is more complex than previous factor analyses have suggested. Our findings point to the dangers in assuming that a factor structure can be generalized beyond the data on which it is based to provide theoretical statements about psychological structure. The new scales appear to be valid because they correlate with demographic variables and indicators of social support in the expected directions.  相似文献   
994.
995.
The control of the ground reaction force vector relative to the center of gravity (CoG) was examined while subjects performed a back-lifting task. Six male subjects (aged 24.0 +/- 2.5 years) repeatedly lifted a barbell. A biomechanical analysis that used a linked segment model revealed that the summed rotations of body segments during lifting yielded a specific rate of change of the angular momentum of the entire body. This equaled the external moment provided by Fsubg; relative to CoG. This implies that multisegment movements involve control of the angular momentum of the entire body through an appropriately directed Fsubg;. Thus, in dynamic tasks Fsubg; is pointed away from rather than lined up with the CoG, as is the case in static tasks.  相似文献   
996.
The published literature on the relationship between behavioral intentions and fertility behavior exhibits four major problems: inconsistent and confusing use of theoretical constructs, limited use of different types of intentions, use of nonbehavioral outcomes, and failure to explore adequately the couple aspects of the intentions/behavior relationship. The study reported here addresses these problems by using a theoretical framework that characterizes the psychological/behavioral sequence leading to a planned conception, three different types of fertility intentions, a behavioral outcome variable, and data from 196 married couples with no children and 185 married couples with one child. Data analysis results in a simultaneous equation, constrained regression model which indicates that child-timing intentions are the most important predictors of proceptive behavior over a 3-1/2 year period and that childbearing intentions are next in importance; that behavioral intentions are the final common pathway through which fertility motivations, attitudes, beliefs, and desires affect behavior; that the use of proceptive behavior as an outcome variable improves the explanatory power of our models; and that the interaction of couple intentions do not demonstrate greater husband or wife influence over couple proceptive behavior but do demonstrate that disagreement has a delaying effect on the onset of that behavior.  相似文献   
997.
998.
Magnitude estimations involving spatial characteristics, such as distance, typically show a compressive function when estimates are made from memory. In particular, as the magnitude of a property grows larger and larger, estimates become more and more inaccurate, with increasing underestimates of the actual magnitude. Previous theories have attempted to explain this difference by supposing that magnitude estimation was accomplished through a reperceptual process, in which the errors of perception are magnified, or a transformation process, in which the memory trace undergoes a consistent alteration toward a more schematic form. The present experiments present evidence in support of an uncertainty hypothesis. When subjects are uncertain of the actual value of a distance, they are forced to guess on the basis of the mean distance they encountered, because they are unable to retrieve the information accurately. When they can retrieve the information, they are more certain and their estimates are more accurate. This hypothesis was also extended to integrative conditions in which the subjects were presented with the stimulus display in a piecemeal fashion. In these cases, distance estimates were derived by combining spatial representations. This method of presentation caused distance estimates to become less accurate.  相似文献   
999.
This paper explores the nature of thematic information made available when a verb is accessed during sentence comprehension. Following Shapiro, Zurif, and Grimshaw (1987), a cross-modal lexical decision (interference) task was employed to examine whether either the number of argument structures or the number of participant (thematic) roles inherent in a verb cause an increase in processing load upon access of the verb. It was determined that there was no evidence for such an increased processing load covarying with the number of argument structures of the verb, at least for those verb types examined in this study. However, there was an increase in processing load as a direct function of the number of participant roles carried by the verb. It is concluded that the participant roles (thematic roles associated with the central meaning of the verb) are stored with the representation of a verb and are made immediately, available upon access of the verb for further processing during comprehension.The first author gratefully acknowledges discussion and advice from Adele Goldberg and the support of grant T32 DC 00041 in pursuing this work. The second author acknowledges the support of NIH grant RO1 DC00494 for the work presented in this paper, and the helpful comments and criticisms of a reviewer.  相似文献   
1000.
The Child Behavior Checklist's (CBCL) applicability to a sample of 105 Russian 9- and 10-year-old children was evaluated by examining the internal consistency of Russian adaptations of parent and teacher report forms. In addition, child behavior scores were correlated with child reports of internalizing symptoms and maternal reports of their own internalizing symptoms and general family functioning. Finally, rates of child behavior problems and patterns of interrater agreement were compared with U.S. normative data. The psychometric properties of the adaptations demonstrate the adequacy of these instruments for use in Russia. Internal consistency and interrater agreement were generally comparable to estimates obtained in U.S. normative samples. Further, an exploration of the construct validity of the Russian versions of the CBCL and Teacher Report Form (TRF) lends additional support to the adequacy of these instruments.This work was supported in part by grants from the International Research Exchanges Board (IREX) (with funds provided by the Andrew Mellon Foundation, the National Endowment for the Humanities, and the U.S. Department of State) and the National Institute of Mental Health (MH-00508, an RSDA to D. Pauls). None of these organizations is responsible for the views expressed. In addition, the authors wish to thank Thomas Achenbach for his helpful comments and suggestions.  相似文献   
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