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941.
In Experiment 1 with 7 autistic children (3 to 6 years old), auditory-visual exclusion was tested with four unknown word-item pairs for each child. One child demonstrated exclusion and positive learning outcomes unequivocally with the four auditory-visual relations. Three children demonstrated exclusion, though inconsistently, and failed to demonstrate positive learning outcomes. The remaining 3 children failed to demonstrate exclusion; therefore, the learning outcome test was omitted. The 6 children who failed to demonstrate exclusion or positive learning outcomes participated in the second experiment. In Experiment 2, nonreinforced exclusion trials with four new unknown word-item pairs were included in trial blocks that also contained reinforced exclusion trials with the unknown exemplars from Experiment 1. Five children demonstrated exclusion with the new word-item pairs, and 4 of these demonstrated positive learning outcomes in further tests. One child demonstrated some limited but inconsistent improvement in exclusion and was not tested for learning outcomes. The data suggest that contemporaneous presentation of multiple examples of reinforced exclusion facilitated nonreinforced exclusion performances and that the resulting reduction in errors was critical in producing accurate learning outcomes with the new word-item discriminations.  相似文献   
942.
Environmental stimuli that set the occasion wherein drugs are acquired can "trigger" drug-related behavior. Investigating the stimulus control of drug self-administration in laboratory animals should help us better understand this aspect of human drug abuse. Stimulus control of cocaine self-administration was generated here for the first time using multiple and chained schedules with short, frequently-alternating components--like those typically used to study food-maintained responding. The procedures and results are presented along with case histories to illustrate the strategies used to produce this stimulus control. All these multicomponent schedules contained variable-interval (VI) components as well as differential-reinforcement-of-other-behavior (DRO) or extinction components. Schedule parameters and unit dose were adjusted for each rat to produce stable, moderate rates in VI components, with minimal postreinforcement (infusion) pausing, and response cessation in extinction and DRO components. Whole-body drug levels on terminal baselines calculated retrospectively revealed that all rats maintained fairly stable drug levels (mean, 2.3 to 3.4 mg/kg) and molar rates of intake (approximately 6.0 mg/kg/hr). Within this range, no relation between local VI response rates and drug level was found. The stimulus control revealed in cumulative records was indistinguishable from that achieved with food under these schedules, suggesting that common mechanisms may underlie the control of cocaine- and food-maintained behavior.  相似文献   
943.
Forgetting functions with 18 delay intervals were generated for delayed matching-to-sample performance in pigeons. Delay interval variation was achieved by arranging five different sets of five delays across daily sessions. In different conditions, the delays were distributed in arithmetic or logarithmic series. There was no convincing evidence for different effects on discriminability of the distributions of different delays. The mean data were better fitted by some mathematical functions than by others, but the best-fitting functions depended on the distribution of delays. In further conditions with a fixed set of five delays, discriminability was higher with a logarithmic distribution of delays than with an arithmetic distribution. This result is consistent with the treatment of the forgetting function in terms of generalization decrement.  相似文献   
944.
We evaluated an enriched teaching program for reducing resistance and indices of unhappiness displayed by 3 individuals with profound multiple disabilities during teaching sessions. The program involved presentation of preferred activities before, during, and after each teaching session, discontinuation of identified nonpreferred activities, and a brief break and preferred activity following occurrence of resistance. Implementation of the enriched teaching program was accompanied by reductions in resistance and indices of unhappiness for each participant. Results also indicated no negative impact of the program on participant performance of the teaching steps or staff teaching proficiency. Staff questionnaire responses provided a degree of social validation for the observed changes in that staff reported the participants liked the enriched teaching program more than the traditional teaching process. Directions for future research discussed include identifying critical aspects of the overall program and the potential relation between teaching proficiency and the program's enrichment effectiveness.  相似文献   
945.
In the signal detection paradigm, the non-parametric index of sensitivity A′, as first introduced by Pollack and Norman (1964), is a popular alternative to the more traditional d′ measure of sensitivity. Smith (1995) clarified a confusion about the interpretation of A′ in relation to the area beneath proper receiver operating characteristic (ROC) curves, and provided a formula (which he called A′′) for this commonly held interpretation. However, he made an error in his calculations. Here, we rectify this error by providing the correct formula (which we call A) and compare the discrepancy that would have resulted. The corresponding measure for bias b is also provided. Since all such calculations apply to “proper” ROC curves with non-decreasing slopes, we also prove, as a separate result, the slope-monotonicity of ROC curves generated by likelihood-ratio criterion.This revised article was published online in August 2005 with the PDF paginated correctly.  相似文献   
946.
The U.S. National Assessment of Educational Progress (NAEP), the Third International Mathematics and Science Study (TIMSS), and the U.S. Adult Literacy Survey collect probability samples of students (or adults) who are administered brief examinations in subject areas such as mathematics and reading (cognitive variables), along with background demographic (primary) and educational environment (secondary) questions. The demographic questions are used in the primary reporting, while the numerous explanatory secondary variables, or covariates, are only directly utilized in subsequent secondary analyses. The covariates are also used indirectly to create the plausible values (multiple imputations) that are an integral part of analyses because of the use of sparse matrix sampling of cognitive items. The improvement in the precision of the primary reporting due to the inclusion of the covariates is assessed here and contrasted with the precision of reporting using plausible values created using only the primary demographic variables.The results demonstrate that the improvement in precision depends on the matrix sampling designs for the cognitive assessments. The improvements range from essentially none for the most common designs, to moderate for some less common designs. Consequently, two potential changes in the reporting procedures that could improve the statistical and operational efficiency of primary reporting are (a) eliminate or reduce the collection of covariates and increase the number of cognitive items, (b) to avoid delays, eliminate the covariates from the creation of plausible values used for the primary reports, but include them later when creating public-use files for secondary analyses. The potential improvements in statistical and operational efficiency must be weighed against the intrinsic interest in the covariates, and the potential for small discrepancies in the primary and secondary reporting.Thanks to Donald Rubin, Robert Mislevy, and John Barnard for their helpful comments and computing assistance. This work was supported by NCES Grant 84.902B980011.  相似文献   
947.
对<系辞>等传中论及人性及其与天道之关系的文字,古今学者的理解各有心得.作者认为,行<系辞>论性语义为一阴一阳的运行变化称之为道,人从天道变化中得到了善,人性使天道赋予人的这种善得到了完成和显现.并且认为,<易传>、<中庸>、<孟子>实际都是认为"性自命出,命从天降"的,都是在人性与天道有一致性的意义上肯定人性善的,故否定<易传>有性善论,以为<易>、<庸>、<孟>的人性说致思路数不同的观点,都是不合实际的.作者又认为,将天道赋予人道正义的意义又返而以支撑人道原则,自<易传>已然,宋儒的天道性命学说与此是一脉相承的,故否定理学与先秦儒学的联系也是不合事实的.作者还认为,中国古代思想家宣扬性善论的主题是弘扬理性,强化人们对人道的自觉与自信,其中凝聚的积极善良的正气,乃是我们民族文化的元神.  相似文献   
948.
949.
Methamphetamine and scopolamine were studied in monkeys responding under a multiple fixed-ratio fixed-interval schedule of reinforcement. A response on any one of six levers could satisfy the schedule requirements. Variability of response location was evaluated in terms of switches, where a switch was defined as a response on one lever followed by a response on a different lever. Under baseline conditions the fixed-ratio schedule generated a high rate of responding and a low level of variability, while the fixed-interval schedule generated a low rate of responding and a high level of variability. Both methamphetamine (0.1 to 0.5 mg/kg) and scopolamine (2.4 to 240 microgram/kg) decreased overall response rate and increased variability of response location in each component of the multiple schedule with increasing doses of drug. At lower doses both drugs were found to decrease rate without affecting response variability.  相似文献   
950.
Most deception research provides between-subject results (e.g., liars give on average less detailed accounts), which might be of limited value for professionals evaluating credibility on an individual basis. This study examines the optimal instructions of a within-subject multiple recalls strategy to detect deception. A total of 110 participants, divided into a Lie and Truth group, were randomly placed into four interview conditions: two Basic report-everything instructions (1), a Basic recall followed by an Open depth instruction (2), a Basic recall followed by the Verifiability Approach and Information Protocol (3), and two recalls with the Verifiability Approach and Information Protocol (4). All recalls were coded for total details and verifiable details. Group (lie and truth) × Recall (first and second) was only significant in condition 3, with truth tellers providing more verifiable details in the second recall than the first. A simple within-subject decision rule was derived, allowing a 76.9% discrimination rate. Professionals can optimally evaluate credibility using two recalls (Basic recall followed by Verifiability Approach and Information Protocol) and observing the evolution of verifiable details.  相似文献   
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