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361.
Communal litter defence by sister and nonsister female mice can provide a valuable experimental paradigm to test whether females invest preferentially in kin. Since females within sister and nonsister pairs have different coefficients of relatedness with the young, the cumulative litter has more fitness value for related than for unrelated partners. Sister and nonsister paired females that gave birth simultaneously (n = 18), or at least within 7 days from each other (n = 12), were tested for maternal aggression on post partum day 7, or 10 days after the first delivery, respectively. Sister (n = 14) and nonsister pairs (n = 16) did not differ in cumulative values of post partum aggression or in the extent to which aggression was balanced within the pair. The aggressive behavior of each female was not correlated with her relative proportion of pups in the litter. Rather, the combined scores of aggression within the pairs were found to be positively correlated with the cumulative litter size. The analysis of mouse litter defence behavior shows that, under conditions of communal nesting, kinship does not seem to affect parental investment in the young significantly. Rather, the cumulative litter size could be used by paired females as a major indicator for parental investment allocation.  相似文献   
362.
Interval estimates of the Pearson, Kendall tau-a and Spearman correlations are reviewed and an improved standard error for the Spearman correlation is proposed. The sample size required to yield a confidence interval having the desired width is examined. A two-stage approximation to the sample size requirement is shown to give accurate results.  相似文献   
363.
FOK判断与可接近信息之间的关系   总被引:6,自引:0,他引:6  
沈大为  韩凯 《心理学报》2001,34(4):33-40
通过三个实验,用语义联想集大小不同的中文单字词研究了靶项目联想集的大小与FOK判断等级和准确性的关系。实验一通过两种不同联想集大小的靶子,比较外显的、提取出的信息和内隐的、语义网络中固有的被激活信息量对FOK判断等级和FOK判断准确性是否有不同的影响。实验二和实验三通过不同的靶子呈现时间和学习遍数,比较不同的识记强度对不同大小联想集的靶子的FOK判断等级和FOK判断准确性的影响。实验结果表明:FOK判断等级随外显的、提取出的信息总量的增多而增高,随内隐的、语义网络中固有的被激活信息量的增多而降低。FOK判断准确性随靶子本身的激活强度的增强而增高,随内隐的、语义网络中固有的被激活信息的激活强度的增强而降低,FOK判断准确性取决于这两种激活强度的综合作用。  相似文献   
364.
超文本节点大小对网页信息搜索效率的影响   总被引:8,自引:1,他引:7  
本研究考察了超文本节点大小对网页信息搜索效率的影响效应.采用单变量被试间设计,自变量为超文本节点大小,分为130字左右、260字左右和520字左右三个水平,因变量为被试找到10个相关问题的正确答案所需的时间以及搜索过程中打开的节点个数和重复节点数.结果表明,虽然发现正确答案所需的时间随节点增大而延长,但这种影响没有达到显著的水平(p>0.05);节点大小对被试打开的节点个数和重复节点数均有显著影响(p<0.01).结论认为,在超文本网页设计中应充分考虑节点大小对信息搜索效率的影响效应.  相似文献   
365.
In the classical test theory, a high-reliability test always leads to a precise measurement. However, when it comes to the prediction of test scores, it is not necessarily so. Based on a Bayesian statistical approach, we predicted the distributions of test scores for a new subject, a new test, and a new subject taking a new test. Under some reasonable conditions, the predicted means, variances, and covariances of predicted scores were obtained and investigated. We found that high test reliability did not necessarily lead to small variances or covariances. For a new subject, higher test reliability led to larger predicted variances and covariances, because high test reliability enabled a more accurate prediction of test score variances. Regarding a new subject taking a new test, in this study, higher test reliability led to a large variance when the sample size was smaller than half the number of tests. The classical test theory is reanalyzed from the viewpoint of predictions and some suggestions are made.  相似文献   
366.
The effects of the size of a stimulus and its eccentricity (central or peripheral) on the visually induced perception of horizontal translational self-motion (vection) were investigated. The central and peripheral areas of the observers' visual field were simultaneously stimulated by random dot patterns that moved in opposite directions. The results of two experiments indicated that the effects of central and peripheral presentations of the moving visual pattern are equivalent, and that vection strength is determined by the stimulus size and speed but not by its eccentricity. These results are consistent with the findings of previous studies that suggested that there are no qualitative differences in the vection-inducing potentials of the central and peripheral areas of the visual field, and are counter to the more traditional hypothesis, which has assumed that the perception of self-motion is specifically assigned to peripheral vision.  相似文献   
367.
During daily 3-hr sessions, 5 rhesus monkeys drank drug solutions and water that were concurrently available. The drug solutions were: 1 milligram per milliliter (mg/mL) pentobarbital (2 monkeys), 1 mg/mL pentobarbital plus 0.5% ethanol (1 monkey), 1 mg/mL pentobarbital plus 1% ethanol (1 monkey), and 8% ethanol (1 monkey). The drug solution and water were available under identical two-component tandem fixed-ratio continuous-reinforcement N schedules. Two variables were manipulated: the size of the fixed-ratio component and the number of liquid deliveries (N) in the second component. Deliveries of the drug solution maintained higher rates of responding than did deliveries of the drug vehicle, water. The number of drug deliveries per session increased with increases in the number of deliveries per fixed ratio and decreased with increases in fixed-ratio size. Analysis of the results in terms of the proportion of deliveries to responses showed that the number of drug deliveries per session was directly related to the size of this quotient. Finally, when fixed-ratio size was repeatedly doubled, the following orderly relationship emerged: The greater the number of available drug deliveries per fixed ratio, the less was the percent decrease in the number of fixed ratios completed per session. It was concluded that increases in the number of liquid deliveries per fixed ratio resulted in increases in reinforcing efficacy.  相似文献   
368.
369.
郭春彦  朱滢 《心理科学》1997,20(5):410-413
利用计算机构造被试总体、模拟实验研究程序进行抽样研究,探讨抽样样本总体达到t检验显著性的数目与统计检验能力之间的一致性。模拟实验结果表明,统计检验能力与样本总体t检验显著性的数目具有很高的一致性,但两者同时受到显著性水平α、样本客量n和总体效果大小δ的影响,从而有可能影响统计推断的可靠性。因此,在进行显著性检验过程中,应对统计检验能力进行估计,这将有利于心理学研究成果的积累。  相似文献   
370.
Estimation of effect size is of interest in many applied fields such as Psychology, Sociology and Education. However there are few nonparametric estimators of effect size proposed in the existing literature, and little is known about the distributional characteristics of these estimators. In this article, two estimators based on the sample quantiles are proposed and studied. The first one is the estimator suggested by Hedges and Olkin (see page 93 of Hedges & Olkin, 1985) for the situation where a treatment effect is evaluated against a control group (Case A). A modified version of the robust estimator by Hedges and Olkin is also proposed for the situation where two parallel treatments are compared (Case B). Large sample distributions of both estimators are derived. Their asymptotic relative efficiencies with respect to the normal maximum likelihood estimators under several common distributions are evaluated. The robust properties of the proposed estimators are discussed with respect to the sample-wise breakdown points proposed by Akritas (1991). Simulation studies are provided in which the performing characteristics of the proposed estimator are compared to that of the nonparametric estimators by Kraemer and Andrews (1982). Interval estimation of the effect sizes is also discussed. In an example, interval estimates for the data set in Kraemer and Andrews (1982) are calculated for both cases A and B.  相似文献   
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