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861.
Hungry, unrestrained rats (N = 7) were rewarded for pressing a response beam in excess of 11 different force requirements. Changes in peak force production as a function of peak force requirement were examined by analyses of the first four moments of distributions of peak response forces: constant error, the within-subject standard deviation, skewness, and kurtosis. Results were similar to those previously obtained with human subjects: Constant error was positive at low and negative at high force requirements, the within-subject standard deviation increased as a negatively accelerating function of force requirement, and skewness and kurtosis were positive at low force requirements and decreased to negative values at the highest increments. Additional analyses of response kinetics indicated that rats, like humans, meet increasing force requirements by altering the rate of rise of force. The performance similarities suggest that common processes are engaged by the human and rat motor control systems to solve the problem of generating forces that are appropriate to the prevailing environmental constraints.  相似文献   
862.
Based on extensive formative research in the three Eastern Caribbean countries of St. Lucia, St. Vincent and the Grenadines, and Grenada (Fishbein, Middlestadt, & Trafimow, 1993; Fishbein, Trafimow, et al., 1993), a three-nation, mass media, condom use campaign was developed. In order to assess the impact of the campaign, a follow-up survey was conducted in St. Vincent and the Grenadines. This paper examines the effectiveness of the campaign by comparing responses on this survey by respondents who were or were not exposed to the campaign. A statistically significant impact of exposure to the campaign was obtained, indicating that a well-designed, empirically based, mass media campaign can be an effective tool in the battle to prevent the spread of AIDS.  相似文献   
863.
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   
864.
Conclusion I have tried to demonstrate that black church defiant spirituality is a complex, multi-dimensional phenomenon. In essence it represents the quest of exiled African peoples to experience ontological harmony with God and all of creation. In the context of a racist society, it has adapted itself to the exigencies of survival and gradual liberation. Specifically, it has sought to reconstruct reality by religiously affirming God's sovereignty over the just and unjust. Also, it has negated black invisibility, subverted political anemia, and now struggles to resist and conquer an encroaching spiritual despair in post-industrial society.I have identified three basic treasures which the black church may offer to other cultures, namely, that care and discipline are the responsibility of every Christian, that authentic Christian worship nurtures commitments to individual and social transformation and it offers a full sensory experience. I close with words from one of America's greatest twentieth century poets, Langston Hughes (1974)—entitled Mother to Son: Well, son, I'll tell you: Life for me ain't been no crystal stair. It's had tacks in it, And splinters, And boards torn up, And places with no carpet on the floor—Bare. But all the time I'se been a-climbin' on, And reachra' landin's, And turnin' corners, And sometimes goin' in the dark Where there ain't been no light. So boy, don't you turn back. Don't you set down on the steps 'Cause you finds it's kinder hard. Don't you fall now —For I'se still goin', honey, I'se still climbin', And life for me ain't been no crystal stair. (p. 187)  相似文献   
865.
Residuals for check of model fit in the polytomous Rasch model are examined. Comparisons are made between using counts for all response pattern and using item totals for score groups for the construction of the residuals. Comparisons are also, for the residuals based on score group totals, made between using as basis the item totals, or using the estimated item parameters. The developed methods are illustrated by two examples, one from a psychiatric rating scale, one from a Danish Welfare Study.  相似文献   
866.
Reviews     
Editor's note: The original edition of the book is (nearly) sold out, but a shortened, updated version will probably be published by Sage Publications, Thousand Oaks CA. Information can be obtained from: T.U.P., P.O. Box 90153, 5000 LE Tilburg, The Netherlands.  相似文献   
867.
A problem which enthusiasts ofIST, Nelson's internal set theory, usually face is how to treat external sets in the internal universe which does not contain them directly. To solve this problem, we considerBST,bounded set theory, a modification ofIST which is, briefly, a theory for the family of thoseIST sets which are members of standard sets.We show thatBST is strong enough to incorporate external sets in the internal universe in a way sufficient to develop the most advanced applications of nonstandard methods. In particular, we define inBST an enlargement of theBST universe which satisfies the axioms ofHST, an external theory close to a theory introduced by Hrbaek. HST includes Replacement and Saturation for all formulas but contradicts the Power Set and Choice axioms (either of them is incompatible with Replacement plus Saturation), therefore to get an external universe which satisfies all ofZFC minus Regularity one has to pay by a restriction of Saturation. We prove thatHST admits a system of subuniverses which modelZFC (minus Regularity but with Power Set and Choice) and Saturation in a form restricted by a fixed but arbitrary standard cardinal.Thus the proposed system of set theoretic foundations for nonstandard mathematics, based on the simple and natural axioms of the internal theoryBST, provides the treatment of external sets sufficient to carry out elaborate external constructions.Partially supported by AMS grants in 1993 and 1994 and DFG grant in 1994.Presented byRobert Goldblatt  相似文献   
868.
We give a set of postulates for the minimal normal modal logicK + without negation or any kind of implication. The connectives are simply , , , . The postulates (and theorems) are all deducibility statements . The only postulates that might not be obvious are
  相似文献   
869.
Three days prior to the 1993 Australian federal election 54 Australian university students who identified with one of the two major political parties were surveyed regarding their perceptions of media campaign impact on self and others. Results provided evidence of a third-person effect (Davison, 1983) wherein respondents judged others us more influenced by the election campaign than themselves. Consistent with predictions derived from social identity theory and self-categorization theory (e.g. Turner, Hogg, Oakes, Reicher and Wetherell, 1987), political ingroup members were also judged as less injuenced by campaign content than political outgroup members. Respondents who identified strongly with their preferred party judged self and ingroup members as less influenced by campaign content than did other respondents, and showed more evidence of positive intergroup differentiation. At the same time, however, these respondents exaggerated self–ingroup differences, challenging the theoretical assumption that intergroup diferentiation is associated with ingroup assimilation. Judgements of media impact on self and other also depended on the direction of the campaign message. Respondents believed ‘voters in general’ were persuaded in line with the intent of campaign content, while outgroup members were seen to be persuaded by material favouring their own side but to be uninfluenced by counter-attitudinal content. Election propaganda, irrespective of direction, was seen to amplify existing party preferences in self and ingroup members. Hence the relative invulnerability of self to media impact was pronounced when respondents judged the impact of pro-outgroup messages. Results suggest that perceptions of self–other differences in media vulnerability are influenced by the subjectively salient social relationship between self and other, and are governed by motivational needs, such as self-esteem, social-identity, and differentiation from others (cf. Brewer, 1991; Hogs and Abrams, 1993).  相似文献   
870.
TODAM2, a theory of distributed associative memory, shows how item and associative information can be considered special cases of serial-order information. Consequently, it is important to get the right model for serial-order information. Here, we analyze and compare three distributed-memory models for serial-order information that use TODAM’s convolution-correlation formalism. These models are the chaining model, the chunking model, and a new model, the power-set model. The chaining model associates each item with its predecessor; the chunking model uses multiple convolutions andn-grams to form chunks; and the power-set model interassociates all items in a set in a particular way to form a chunk. The models are compared in terms of their performance on seven basic tests of serial-order information—namely, serial recall, backward recall, recall of missing items, sequential probe tests, positional probe tests, serial-to-paired-associate transfer, and item recognition. The strengths and weaknesses of each model are discussed.  相似文献   
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