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991.
This article reviews literature concerning functional changes resulting from elevated blood pressure, from reduction of blood pressure, and as a result of the medications used to treat high blood pressure. The research reviewed includes the areas of psychomotor speed, intelligence and cognitive processing, sensory and perceptual processes, and emotional and interpersonal behaviors. The conclusions reached are that the deficits noted to date in hypertensive individuals are not extreme nor are they specific. The greatest disadvantage, however, appears in the area of response speed.  相似文献   
992.
A power function equation between ratios of behavior and ratios of reinforcement rates has been called a generalized form of Herrnstein's (1961) matching law, even without a formal relationship having been shown between the two equations. The present work uses a functional relationship to prove that when ratios of reinforcement are not equivalent to ratios of behavior, and the transform leading to this inequality is consistent for every pair of reinforcement rates, the result is a power function relationship between response and reinforcement ratios. The label “generalized matching equation” for the power function equation is thus validated formally.  相似文献   
993.
A method is given for the least squares regression of a squared variabled 2 on the squared variable 02, where the relation between 0 andd is linear. The problem arises in MDS-algorithms where the loss function is defined in terms of squared distances (e.g., ALSCAL). It is pointed out that the Lagrangian multiplier is a root of fourth degree polynomial.  相似文献   
994.
This study was designed to assess the transfer of treatment gains of autistic children across settings. In the first phase, each of 10 autistic children learned a new behavior in a treatment room and transfer to a novel extra-therapy setting was assessed. Four of the 10 children showed no transfer to the novel setting. Therefore, in the second phase, each child who failed to transfer participated in an analysis of stimulus control in order to determine the variables influencing the deficit in transfer. Each of the four children who did not transfer were selectively responding to an incidental stimulus during the original training in the treatment room. Utilizing a reversal design, each of the four children responded correctly in the extra-therapy setting when the stimulus that was functional during training was identified and introduced into the extra-therapy setting. The extreme selective responding and the resulting bizarre stimulus control found are discussed in relation to the issue of setting generality of treatment gains.  相似文献   
995.
One-hundred-and-sixty adolescents participated in two studies designed to investigate the relationship between IE and helping behavior as mediated by the perceived cause of another's need. In the first study, Ss were given the opportunity to help, either “indirectly” or “directly,” a supervisor who had been over- or underpaid in a prior similar task. Internals helped more in the “direct” help than the “indirect” help conditions but their helping behavior and their perceptions of their supervisors were not consistent. The perceptions of the externals were relatively consistent with their greater help of the “overpaid” supervisor. In study 2, the Ss were given additional information to increase the possibility of their making causal attributions as a function of the supervisor's prior fate. Once again, the external subjects' helping behavior reflected their perception of their supervisor's merit. The internal subjects exhibited relatively little helping behavior regardless of their supervisors' prior fate or perceived competence.  相似文献   
996.
Ab Mooijaart 《Psychometrika》1984,49(1):143-145
FACTALS is a nonmetric common factor analysis model for multivariate data whose variables may be nominal, ordinal or interval. In FACTALS an Alternating Least Squares algorithm is utilized which is claimed to be monotonically convergent.In this paper it is shown that this algorithm is based upon an erroneous assumption, namely that the least squares loss function (which is in this case a nonscale free loss function) can be transformed into a scalefree loss function. A consequence of this is that monotonical convergence of the algorithm can not be guaranteed.  相似文献   
997.
Using an operant analogue of the yes-no detection task, six pigeons were trained to detect luminance changes under two different reinforcement-scheduling procedures. In the first, an uncontrolled reinforcement-ratio procedure, the relative frequency of food reinforcers obtained for correct detections was free to vary with the birds' behavior as luminance levels were changed. In the second, a controlled reinforcement-ratio procedure, changes in preference could not alter the relative distribution of food reinforcers between the two response alternatives. Extreme response biases developed as luminance was decreased to threshold in the uncontrolled procedure. No progressive changes in response bias as a function of decreasing luminance were seen in the controlled procedure. Absolute thresholds for light intensity were lower in the controlled than in the uncontrolled procedure.  相似文献   
998.
The purposes of this experiment were to determine whether (a) it would require fewer trials to teach verbal production of coin values directly or to teach auditory comprehension first, (b) comprehension training would generalize or transfer to production, and (c) production training would generalize to comprehension. Fourteen mentally retarded subjects participated. Their mean mental age was 4.83 yr (SD = 1.83), their mean chronological age was 12.67 yr (SD = 3.17), their mean IQ was 43.86 (SD = 7.81), and their mean arithmetic grade level was Kindergarten 0.1. A matched groups pretest-posttest design, as well as a multiple baseline across responses within each group were employed. The Comprehension-Production Group received coin-value training using two procedures sequentially: auditory comprehension (pointing to the correct coins in response to their verbally stated value) followed by verbal production (verbally stating the coins' value in response to a pointing prompt). The Production Group was trained on the production procedure only. Each subject was repeatedly administered coin-value comprehension and coin-value production tests, which provided the dependent measures. The results indicated that the two experimental groups improved significantly in their comprehension and production of coin values from pretest to posttest and maintained those increments on one- and four-week followup tests. Mean group performance on four-week followups ranged from 89 to 96% correct for the two dependent measures and two groups. Multiple-baseline data showed pronounced increases in performance only after training was initiated on a particular coin. A comparison of the number of trials required for both groups to complete their respective training programs indicated that teaching production alone (X? trials = 137.42) was significantly more efficient than training both comprehension and production (X? = 281.71). The failure of the comprehension procedure to facilitate production acquisition was evidenced by the fact that the Comprehension-Production Group required as many verbal naming trials to achieve mastery as did the Production Group. On the other hand, there was generalization from production training to comprehension. Subjects in the Production Group who were not trained to point to the coins in response to verbal instruction averaged 99% correct on the comprehension test. Research to this point may suggest an interaction between mental level and direction of transfer. The mentally retarded may experience facilitation from production to comprehension training, and for the nonretarded, the direction of transfer may be the converse.  相似文献   
999.
During autoshaping, a 6-second presentation of one stimulus and a variable time 30-second presentation of a second stimulus alternated in appearance on a pigeon key. Grain always was delivered for 3 seconds at the end of the first stimulus interval. In the first experiment, autoshaped pecking of the stimulus preceding grain delivery began much sooner when that stimulus was a black vertical line on a white background and the other stimulus was green than when the opposite stimulus arrangement was used. Because these two stimuli differed in form, hue, brightness, and similarity in hue and brightness to the illumination of the raised feeder, three subsequent experiments examined whether the differential speed of autoshaping in the two groups was due to a feature-positive, feature-negative effect, a preference for brighter over darker stimuli, a simple preference for white over green, or stimulus generalization from the brightness or hue of the illuminated, raised feeder to the stimulus on the key preceding grain delivery. The data from these experiments showed that the first autoshaped key peck was most likely to be made to the stimulus of the same hue as that illuminating the feeder, regardless of whether that stimulus was positively or negatively associated with grain delivery. At least under some conditions, therefore, stimulus-generalization mediated response transfer of pecking grain in the presence of the hue illuminating the feeder to pecking the key illuminated by a similar hue appears to account for the occurrence of autoshaped key pecking.  相似文献   
1000.
项目难度与被试能力分布最优匹配的模拟研究   总被引:2,自引:1,他引:1  
李金波  王权 《心理学报》1998,31(2):197-203
该文运用蒙特卡罗方法对被测试能力分布与测验项目难度分布的匹配问题进行模拟分析,分析表明当能力分布为正态分布正偏态分布和负偏态分布时分别与测验项目难度分布与为正态分布,正偏态分布和负偏态分布匹配,比别的匹配有更高测验期望信息值,测验最大信息测验 系数,并且测验信息曲线最大值的能力点与能力分布的众数愈相一致,测验项目参数估计值性真实值的相关也更高。  相似文献   
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