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11.
Token reinforcement, choice, and self-control in pigeons.   总被引:9,自引:9,他引:0       下载免费PDF全文
Pigeons were exposed to self-control procedures that involved illumination of light-emitting diodes (LEDs) as a form of token reinforcement. In a discrete-trials arrangement, subjects chose between one and three LEDs; each LED was exchangeable for 2-s access to food during distinct posttrial exchange periods. In Experiment 1, subjects generally preferred the immediate presentation of a single LED over the delayed presentation of three LEDs, but differences in the delay to the exchange period between the two options prevented a clear assessment of the relative influence of LED delay and exchange-period delay as determinants of choice. In Experiment 2, in which delays to the exchange period from either alternative were equal in most conditions, all subjects preferred the delayed three LEDs more often than in Experiment-1. In Experiment 3, subjects preferred the option that resulted in a greater amount of food more often if the choices also produced LEDs than if they did not. In Experiment 4, preference for the delayed three LEDs was obtained when delays to the exchange period were equal, but reversed in favor of an immediate single LED when the latter choice also resulted in quicker access to exchange periods. The overall pattern of results suggests that (a) delay to the exchange period is a more critical determinant of choice than is delay to token presentation; (b) tokens may function as conditioned reinforcers, although their discriminative properties may be responsible for the self-control that occurs under token reinforcer arrangements; and (c) previously reported differences in the self-control choices of humans and pigeons may have resulted at least in part from the procedural conventions of using token reinforcers with human subjects and food reinforcers with pigeon subjects.  相似文献   
12.
Given a variety we study the existence of a class such that S1 every A can be represented as a global subdirect product with factors in and S2 every non-trivial A is globally indecomposable. We show that the following varieties (and its subvarieties) have a class satisfying properties S1 and S2: p-algebras, distributive double p-algebras of a finite range, semisimple varieties of lattice expansions such that the simple members form a universal class (bounded distributive lattices, De Morgan algebras, etc) and arithmetical varieties in which the finitely subdirectly irreducible algebras form a universal class (f-rings, vector groups, Wajsberg algebras, discriminator varieties, Heyting algebras, etc). As an application we obtain results analogous to that of Nachbin saying that if every chain of prime filters of a bounded distributive lattice has at most length 1, then the lattice is Boolean.We wish to thank Lic. Alfredo Guerin and Dr. Daniel Penazzi for helping us with linguistics aspects. We are indebted to the referee for several helpful suggestions. We also wish to thank Professor Mick Adams for providing us with several reprints and useful e-mail information on the subject.Suported by CONICOR and SECyT (UNC).  相似文献   
13.
Introduction and overview: Global information ethics   总被引:2,自引:0,他引:2  
This is an introduction to a set of papers on Computer Ethics from the conference ETHICOMP95. Taken as a whole, the collection of papers provides arguments and concepts to launch a new development in computer ethics: ‘Global Information Ethics’. A rationale for globalization is provided, as well as some early efforts which move in that direction. ETHICOMP95, an international conference on Computer Ethics, was held 28–30 March 1995 at De Montfort University, Leicester, UK. Co-directors were Terrell Ward Bynum and Simon Rogerson.  相似文献   
14.
In general, nonlinear models such as those commonly employed for the analysis of covariance structures, are not globally identifiable. Any investigation of local identifiability must either yield a mapping of identifiability onto the entire parameter space, which will rarely be feasible in any applications of interest, or confine itself to the neighbourhood of such points of special interest as the maximum likelihood point.The author would like to thank J. Jack McArdle and Colin Fraser for their comments on this paper.  相似文献   
15.
The effects of a good-behavior contract on the on-task behavior, disruptive behavior, daily assignment completion, and weekly grades of four sixth-grade students were examined in a public school classroom. The contract consisted of presenting the students with a list of good conduct and assignment completion goals and a list of disruptive behaviors coupled with a list of rewards and penalties that could be earned. The rewards and penalties made use of existing facilities and classroom privileges. At the beginning of each morning work period, the teacher negotiated the good-behavior contract with each experimental subject. During the negotiations, the teacher emphasized student self-management and encouraged each student to earn a reward by achieving the good-conduct goals and completing the contract assignments. An isolated work area was provided to allow students the opportunity to remove themselves from their desks for a fixed period of 15 min. At the end of the work period, the teacher determined whether each student earned a choice of reward or penalty dependent on assignment completion and whether the teacher had observed disruptive behaviors. Thus, the contract permitted the student to negotiate the goal behaviors and contingencies with the teacher. Throughout the study, the students were in agreement with the teacher on whether a choice of reward or penalty had been earned. The contract was introduced for different children at different times, constituting a multiple-baseline analysis. On-task behavior and daily assignment completion increased, weekly grades were higher, and disruptive behavior decreased when the contract was in effect. Three contrast subjects were selected from the class as model students who consistently produced acceptable assignments and who did not engage in high rates of disruptive and/or off-task behaviors. When the contract was in effect for the experimental subjects, their performance compared favorably with the contrast subjects, who never received the daily contract. The results demonstrated that the contract was effective within the confines of the facilities and contingencies readily available in a public school classroom setting.  相似文献   
16.
Self-reinforcement in operant situations generally refers to those arrangements in which the subject delivers to himself a consequence, contingent on his behavior. However, it is noted that the definition of all other types of reinforcement make its delivery contingent on the subject's behavior. What is actually at issue is the agent who defines whether or not the response required for reinforcement has been met. In self-reinforcement, the subject himself defines this. In the laboratory, this requirement is machine-defined; in school examinations, it is teacher-defined; and in many clinical self-control situations, it is also independently defined. A reinforcement contingency presupposes such independence, absent in self-reinforcement. Implications for research and practice are discussed and alternative formulations are offered.  相似文献   
17.
18.
In this paper I discuss Jungian psychological work of the trauma and loss experienced in reaction to COVID-19 with a man who represents a clinical composite. The issues of precarity, a concept used by the philosopher Judith Butler, are combined with the notions of lack and absence of French psychoanalyst André Green. The psychological and societal situation of precarity aroused the man’s childhood issues that were long repressed. The loneliness, isolation and death from COVID-19 mirrored his personal and the collective responses to the disaster from this global pandemic. He felt on the edge of collapse as what he knew of his world crashed and he found himself unable to cope. The subsequent Jungian work taking place through the virtual computer screen was taxing and restorative simultaneously for both analyst and analysand.  相似文献   
19.
采用父母教养方式问卷、手机依赖指数量表、自我控制量表和感觉寻求问卷,对426名在校大学生进行测查,以探讨父母教养方式与大学生手机依赖的关系及自我控制和感觉寻求的作用。结果发现:(1)父母拒绝和过度保护与手机依赖正相关,而父母情感温暖、理解与手机依赖负相关;(2)自我控制和感觉寻求在父母教养方式与大学生手机依赖间分别起部分中介作用;(3)自我控制和感觉寻求在父母教养方式与大学生手机依赖间起链式中介作用。结果表明父母教养方式与大学生手机依赖具有密切联系,自我控制和感觉寻求在该联系中起重要作用。  相似文献   
20.
采用追踪设计对439名儿童的父母进行问卷调查,旨在考察父母教养方式对学前儿童社会适应的影响及可能的中介机制。在第一年时,父母分别报告了自己的教养方式和儿童的社会适应;在第二年时,父母分别报告了儿童的自我控制和社会适应。研究结果表明:(1)父母权威型教养方式得分越高,孩子的社会适应越好,而父母专制型和放任型教养方式得分越高,孩子的社会适应越差;(2)自我控制能力高的孩子的亲社会行为更多,问题行为更少;(3)自我控制在母亲专制型教养方式与儿童违纪攻击和敏感合作间起完全中介作用,自我控制在父亲放任型教养方式与儿童违纪攻击和害羞焦虑间起完全中介作用。  相似文献   
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