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271.
Dexin Shi Hairong Song Christine DiStefano Alberto Maydeu-Olivares Heather L. McDaniel 《Multivariate behavioral research》2019,54(2):224-245
In this study, we introduce an interval estimation approach based on Bayesian structural equation modeling to evaluate factorial invariance. For each tested parameter, the size of noninvariance with an uncertainty interval (i.e. highest density interval [HDI]) is assessed via Bayesian parameter estimation. By comparing the most credible values (i.e. 95% HDI) with a region of practical equivalence (ROPE), the Bayesian approach allows researchers to (1) support the null hypothesis of practical invariance, and (2) examine the practical importance of the noninvariant parameter. Compared to the traditional likelihood ratio test, simulation results suggested that the proposed Bayesian approach could offer additional insight into evaluating factorial invariance, thus, leading to more informative conclusions. We provide an empirical example to demonstrate the procedures necessary to implement the proposed method in applied research. The importance of and influences on the choice of an appropriate ROPE are discussed. 相似文献
272.
Research with infants is often slow and time-consuming, so infant researchers face great pressure to use the available participants in an efficient way. One strategy that researchers sometimes use to optimize efficiency is data peeking (or “optional stopping”), that is, doing a preliminary analysis (whether a formal significance test or informal eyeballing) of collected data. Data peeking helps researchers decide whether to abandon or tweak a study, decide that a sample is complete, or decide to continue adding data points. Unfortunately, data peeking can have negative consequences such as increased rates of false positives (wrongly concluding that an effect is present when it is not). We argue that, with simple corrections, the benefits of data peeking can be harnessed to use participants more efficiently. We review two corrections that can be transparently reported: one can be applied at the beginning of a study to lay out a plan for data peeking, and a second can be applied after data collection has already started. These corrections are easy to implement in the current framework of infancy research. The use of these corrections, together with transparent reporting, can increase the replicability of infant research. 相似文献
273.
Social discounting was measured as the amount of money a participant was willing to forgo to give a fixed amount (usually $75) to another person. In the first experiment, amount forgone was a hyperbolic function of the social distance between the giver and receiver. In the second experiment, degree of social discounting was an increasing function of reward magnitude whereas degree of delay discounting was a decreasing function of reward magnitude. In the third experiment, the shape of the function relating delayed rewards to equally valued immediate rewards for another person was predicted from individual delay and social discount functions. All in all, the studies show that the social discount function, like delay and probability discount functions, is hyperbolic in form. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
274.
本研究深入考察了我国现阶段小学儿童算术估算能力的发展状况。通过运用自编材料对1027名儿童的团体与个别测试,发现其估算能力的发展具有如下特点:(1)明显受到题目类型的影响,但在不同年龄阶段影响又不尽相同。(2)三年级可能是整数和小数估算能力发展的一个关键期,五年级是发展分数估算能力的较好时期。(3)不同估算策略的发展进程差别相当大,不同时期都有发展的侧重点。(4)小学儿童在估算时易发生多种错误,而且不同年级均有一些典型错误。另外研究还对儿童估算能力、策略与错误类型的发展进行了深入讨论。 相似文献
275.
Nonparametric Estimation of Standard Errors in Covariance Analysis Using the Infinitesimal Jackknife
Robert I. Jennrich 《Psychometrika》2008,73(4):579-594
The infinitesimal jackknife provides a simple general method for estimating standard errors in covariance structure analysis.
Beyond its simplicity and generality what makes the infinitesimal jackknife method attractive is that essentially no assumptions
are required to produce consistent standard error estimates, not even the requirement that the population sampled has the
covariance structure assumed. Commonly used covariance structure analysis software uses parametric methods for estimating
parameters and standard errors. When the population sampled has the covariance structure assumed, but fails to have the distributional
form assumed, the parameter estimates usually remain consistent, but the standard error estimates do not. This has motivated
the introduction of a variety of nonparametric standard error estimates that are consistent when the population sampled fails
to have the distributional form assumed. The only distributional assumption these require is that the covariance structure
be correctly specified. As noted, even this assumption is not required for the infinitesimal jackknife. The relation between
the infinitesimal jackknife and other nonparametric standard error estimators is discussed. An advantage of the infinitesimal
jackknife over the jackknife and the bootstrap is that it requires only one analysis to produce standard error estimates rather
than one for every jackknife or bootstrap sample. 相似文献
276.
Methods of incorporating a ridge type of regularization into partial redundancy analysis (PRA), constrained redundancy analysis
(CRA), and partial and constrained redundancy analysis (PCRA) were discussed. The usefulness of ridge estimation in reducing
mean square error (MSE) has been recognized in multiple regression analysis for some time, especially when predictor variables
are nearly collinear, and the ordinary least squares estimator is poorly determined. The ridge estimation method was extended
to PRA, CRA, and PCRA, where the reduced rank ridge estimates of regression coefficients were obtained by minimizing the ridge
least squares criterion. It was shown that in all cases they could be obtained in closed form for a fixed value of ridge parameter.
An optimal value of the ridge parameter is found by G-fold cross validation. Illustrative examples were given to demonstrate the usefulness of the method in practical data analysis
situations.
We thank Jim Ramsay for his insightful comments on an earlier draft of this paper. The work reported in this paper is supported
by Grants 10630 from the Natural Sciences and Engineering Research Council of Canada to the first author. 相似文献
277.
278.
变通的题组项目功能差异检验方法在篇章阅读测验中的应用 总被引:1,自引:0,他引:1
篇章形式的阅读测验在语文学科考试与语言能力测试中占有越来越重要的地位。篇章阅读测验是一种典型的题组测验, 因此需要采用能够处理题组效应的统计方法进行分析。在进行项目功能差异(DIF)检验时, 也需要采用与之匹配的DIF检验方法。目前能够处理题组效应的DIF检验方法主要包括变通的题组DIF检验方法和基于题组反应模型的DIF检验方法, 基于题组反应模型的DIF检验方法由于实现过程繁琐, 目前只停留在理论探讨阶段。本研究将变通的题组DIF检验方法及其效应值指标引入篇章阅读测验的DIF检验中, 能够解决篇章阅读测验中DIF检验与测量的问题, 效应值指标能够为如何处理有DIF效应的题组项目提供重要依据。本研究首先选用非题组DIF检验方法与变通的题组DIF检验方法对一份试卷进行DIF检验, 两种方法的比较结果体现了进行题组DIF检验的必要性与优越性, 然后选用变通的题组DIF检验方法中有代表性的四种方法对某阅读成就测验进行题组DIF检验。研究结果表明, 在篇章阅读测验中, 能够处理题组效应的DIF检验方法较传统的DIF检验方法具有较大的优越性。 相似文献
279.
心算活动中混合策略选择的ERP研究 总被引:1,自引:0,他引:1
考察问题大小、距离、奇偶及答案正误对心算策略选择的影响。采用先答案后算式的呈现方式, 记录了15名被试的64导ERP。研究发现, 在小问题中, 错误答案与正确答案相比, 诱发了算术不一致N400, 距离和奇偶因素影响其波峰及潜伏期。在大问题中, 距离和奇偶因素影响晚期正波, 近距离奇偶一致情境诱发了波幅较小的晚期正慢波。表明在混合情境, 距离比奇偶信息优先得到加工; 在小问题心算中距离和奇偶信息影响答案提取, 而在大问题心算中, 对于依靠距离信息较难直接判断的小距离问题, 在进一步的加工中会借助奇偶信息判断是否采用精确计算策略。 相似文献
280.