Discrimination of methadone and cocaine by pigeons without explicit discrimination training.

Pigeons were trained to peck a key on a variable-interval 2-min schedule of food reinforcement. Prior to each session, either 2.0 mg/kg methadone (n = 3), 3.0 mg/kg cocaine (n = 4), or 5.6 mg/kg cocaine (n = 2) was administered. When each pigeon's rate of pecking was stable, a range of doses of the training drug and saline were administered prior to 20-min extinction sessions separated by at least four training sessions. Rate of pecking during these extinction tests was generally an increasing function of dose, with the lowest rates obtained following saline and low doses and the highest rates obtained following doses near the training doses. Dose functions from pigeons trained with 5.6 mg/kg cocaine were steeper than those from pigeons trained with 3.0 mg/kg cocaine. Pigeons trained with methadone or 3.0 mg/kg cocaine were then given discrimination training, in which food reinforcement followed drug administration and 20-min extinction sessions followed saline administration. Rates of pecking under these conditions quickly diverged until near-zero rates were obtained following saline and high rates were obtained following drug. Discrimination training steepened dose functions for the training drugs, and the effects of several other substituted drugs depended on the pharmacology of the training drug. The pigeons trained with 5.6 mg/kg cocaine were tested with d-amphetamine, methadone, and morphine prior to discrimination training. d-Amphetamine increased rates dose dependently, and methadone and morphine did not. The results suggest that discriminative control by methadone and cocaine was established without explicit discrimination training.     

General education,cultural diversity,and identity

The issue of this paper is cultural plurality as a problem for public, general education and for (personal) identity. In order to examine this question, one needs to be clear about the meaning of the concepts of general education, on the one hand, and cultural diversity on the other. In the first section, we will fix the meaning of these concepts. A conceptual distinction between cultural diversity and cultural pluralism will be introduced. In the second section, it will be argued that open pluralism can only be maintained if there is a basic common culture apart from the cultural diversity that pluralism affirms. Therefore, there is yet an indispensable role for general education in an open, pluralistic society. In the third section we will look at two metaphors that give an opposite significance to the relation between identity and diversity: the conversational metaphor and the food metaphor mishmash. The final section expands on the conversational metaphor by way of an exposition of Ricoeur's hermeneutics of the self. It supplies us with a promising concept of identity that is not in complete opposition to diversity.     

TEACHING MULTIPLICATION FACTS TO STUDENTS WITH LEARNING DISABILITIES

Multiple baseline designs were used to examine the effects of an instructional package on accuracy of performance in solving multiplication facts by 3 students with learning disabilities. The instructional package included the following components: (a) a modified instructional sequence in which multiplication facts were grouped into the zeros, ones, doubles, fives, and nines categories, and those remaining; (b) identification of the category in which each fact belonged; (c) mnemonic strategies associated with solving facts in each category; and (d) steps to be completed for solving facts in each category. Results indicated that the instructional package produced substantial and immediate effects. After receiving instruction, a participant's accuracy was often 100%, and this was maintained throughout the evaluation even as other strategies were introduced. Comparable results occurred across students, demonstrating replication of the effects of the instructional package.     

弱智儿童感知动作技能特点的实验研究

本研究以难易程度不同的两个打洞操作作业 ,对弱智儿童和正常儿童的感知 动作技能进行了多种参数的测查。结果发现 :两类儿童在理解操作要点、操作速度、操作动作协调性以及操作正确性等各个方面都有明显的差异。同时通过比较 ,对弱智儿童感知 动作技能的特点 ,从外部肢体动作方式和内部智力动作方式两方面进行了详细的分析 ,并在此基础上对弱智儿童的感知 动作技能的教育与训练提出了建议 ,这对弱智学校改革教学、提高教学质量具有重要意义。     

影响学习迁移的几个因素的实验研究

针对前人较多地从学习材料本身的特点或学习者的心理特点出发去孤立地考察对学习迁移的影响这一现象 ,本研究试采用代数运算材料 ,系统地探讨了学习材料的相同要素和学习者概括化认知过程两者之间的内在关系 ,并将相同要素进一步区分为表述形式相似和内在原理相似。旨在对较为复杂的认知学习中迁移的影响因素做更深入的考察。结果表明 :①概括化和相同要素对学习迁移的影响依然存在 ,但需作具体分析。其中 ,前者应成为影响学习迁移的更重要因素。②在学习材料的相同要素中 ,实质上对迁移起作用的是内在原理相似性 ;而表述形式相似性不起主要作用。③概括化因素和内在原理相似性因素之间的交互作用对学习迁移影响极大。     

Improving the spelling performance of students with disabilities

The present study examined the effects of an error correction strategy on the spelling accuracy of students with emotional and/or learning disabilities. The strategy, which asked students to spell a word, view a correct model, and then correct their errors, was compared to a traditional strategy that asked students to write words three times each while viewing a correct model. Results showed that students learned more words in the error correction condition than in the traditional condition. The error correction treatment was shown to be an effective strategy that reduced the number of repetitive spelling practice trials, and was preferred by students.     

Stability criteria

Three approaches to the determination of behavioral stability were examined. In the first, a learning curve was fit to acquisition data (from Cumming and Schoenfeld, 1960), and the “experiment” stopped when the data approached sufficiently close to the theoretical asymptote. In the second, the data were analyzed for variability and linear and quadratic trend. In the third, the experiment was stopped when the magnitude of the daily changes in the data fell below a criterion. Accuracy was measured as deviation between the average value of the dependent variable when the experiment was stopped, and the average value over the last 100 sessions. The first approach was most accurate, but at the cost of requiring the most sessions and being the most difficult to apply. Both the second and third approaches provided acceptable criteria with a reasonable cost-accuracy tradeoff. The second approach permits a continuous adjustment of the criteria to accommodate the variability intrinsic in the experimental paradigm. The third, nomothetic, approach also takes into account the decreasing marginal utility of extended training sessions.     

Robust estimation of ability in the Rasch model

Estimating ability parameters in latent trait models in general, and in the Rasch model in particular is almost always hampered by noise in the data. This noise can be caused by guessing, inattention to easy questions, and other factors which are unrelated to ability. In this study several alternative formulations which attempt to deal with these problems without a reparameterization are tested through a Monte Carlo simulation. It was found that although no one of the tested schemes is uniformly superior to all others, a modified jackknife stood out as the best one in general, it was also super efficient (more efficient than the asymptotically optimal estimator) for tests with forty or fewer items. It is proposed that this sort of jackknifing scheme for estimating ability be considered for practical work.This research was funded through a grant from the Law Enforcement Assistance Administration (78-NI-AX-0047) to the Bureau of Social Science Research, Howard Wainer, Principal Investigator. We would like to thank Ronald Mead, Anne Morgan and James Ramsay for kind, generous, and invaluable help at various stages of the project.     

Effects of knowledge that attributions will be observed by others

The current study was conducted to determine if attribution statements would be affected by subjects' knowledge that their attributions of success or failure would be observed by an opposite-sex peer. At the time subjects recorded their attributions, half of them anticipated that their attributions would soon be observed in their presence by an opposite-sex peer, while the other half recorded their attributions anonymously. Results indicated that attributions of success and failure were affected by the social context. Observed subjects evidenced less tendency to attribute their failure to low ability than did nonobserved subjects. Subjects who succeeded on an identity-relevant task reported higher ability attributions under observation conditions than under nonobservation conditions. Observed subjects evidenced significantly greater willingness to attribute failure to lack of effort than did nonobserved subjects. For a task intended to be of minimal relevance to subjects' identities, nonobserved subjects attributed failure to task difficulty to a significantly greater degree than did observed subjects. Results were discussed in relation to Bradley's contention that self-serving biases in attribution can usefully be conceptualized as strategic self-presentations.