全文获取类型
收费全文 | 388篇 |
免费 | 127篇 |
国内免费 | 41篇 |
专业分类
556篇 |
出版年
2023年 | 7篇 |
2022年 | 7篇 |
2021年 | 11篇 |
2020年 | 10篇 |
2019年 | 12篇 |
2018年 | 16篇 |
2017年 | 23篇 |
2016年 | 17篇 |
2015年 | 14篇 |
2014年 | 15篇 |
2013年 | 37篇 |
2012年 | 15篇 |
2011年 | 22篇 |
2010年 | 12篇 |
2009年 | 22篇 |
2008年 | 11篇 |
2007年 | 11篇 |
2006年 | 20篇 |
2005年 | 21篇 |
2004年 | 8篇 |
2003年 | 8篇 |
2002年 | 15篇 |
2001年 | 12篇 |
2000年 | 12篇 |
1999年 | 6篇 |
1998年 | 7篇 |
1997年 | 7篇 |
1996年 | 8篇 |
1995年 | 7篇 |
1994年 | 7篇 |
1993年 | 8篇 |
1992年 | 12篇 |
1991年 | 12篇 |
1990年 | 9篇 |
1989年 | 14篇 |
1988年 | 13篇 |
1987年 | 11篇 |
1986年 | 11篇 |
1985年 | 9篇 |
1984年 | 7篇 |
1983年 | 8篇 |
1982年 | 4篇 |
1981年 | 4篇 |
1980年 | 4篇 |
1979年 | 9篇 |
1978年 | 10篇 |
1977年 | 5篇 |
1976年 | 5篇 |
1975年 | 1篇 |
排序方式: 共有556条查询结果,搜索用时 0 毫秒
461.
462.
463.
We tested the relationship between flourishing and positivity ratio while accounting for different measures of affect and rating scale formats. We further examined age-related differences in positivity ratio. Studies 1 and 2 showed that positivity ratio is affected by the measure used, but not by the rating scale format. Study 3 further showed that positivity ratio is higher among older adults. The above pattern of methodological variations was replicated in Study 4 with daily ratings of emotions and in Study 5 where emotions were rated on an extended scale. Study 5 also replicated the aforementioned age effect. Together these studies suggest that positivity ratio is moderated by methodological variants and individual differences, such as chronological age. Future studies should account for these possible moderation effects when exploring the positivity ratio and its relationship to flourishing. 相似文献
464.
Kathryn R. Glodowski Jason Bourret Jonathan W. Ivy Jonathan P. Seaver Joshua Jackson Julie M. Stine Andrew E. Nuzzolilli 《Behavioral Interventions》2020,35(1):25-37
Token schedules of reinforcement are ubiquitous in clinical settings, yet little research has thoroughly evaluated the effects of token schedules on responding in clinical settings. Basic research has shown token schedules of reinforcement produce lower response rates and larger pre‐ratio pauses compared to tandem schedules. The purpose of the current study was to determine whether the same effects are produced with adolescents with autism or related disorders. We examined response patterns under otherwise identical FR token and FR tandem schedules. Tokens suppressed responding for one participant only under high schedule values and for a second participant under common clinical schedule values; no difference in responding occurred between token and tandem schedules for two participants. These results support the systematic evaluation of token schedules of reinforcement in clinical settings. Additional applied research is needed on token schedules to further our understanding of the underlying mechanisms that contribute to the overall effectiveness of token economies. 相似文献
465.
Current practice in factor analysis typically involves analysis of correlation rather than covariance matrices. We study whether the standardz-statistic that evaluates whether a factor loading is statistically necessary is correctly applied in such situations and more generally when the variables being analyzed are arbitrarily rescaled. Effects of rescaling on estimated standard errors of factor loading estimates, and the consequent effect onz-statistics, are studied in three variants of the classical exploratory factor model under canonical, raw varimax, and normal varimax solutions. For models with analytical solutions we find that some of the standard errors as well as their estimates are scale equivariant, while others are invariant. For a model in which an analytical solution does not exist, we use an example to illustrate that neither the factor loading estimates nor the standard error estimates possess scale equivariance or invariance, implying that different conclusions could be obtained with different scalings. Together with the prior findings on parameter estimates, these results provide new guidance for a key statistical aspect of factor analysis.We gratefully acknowledge the help of the Associate Editor and three referees whose constructive comments lead to an improved version of the paper. This work was supported by National Institute on Drug Abuse Grants DA01070 and DA00017 and by the University of North Texas Faculty Research Grant Program. 相似文献
466.
When modeling the relationship between two nominal categorical variables, it is often desirable to include covariates to understand
how individuals differ in their response behavior. Typically, however, not all the relevant covariates are available, with
the result that the measured variables cannot fully account for the associations between the nominal variables. Under the
assumption that the observed and unobserved variables follow a homogeneous conditional Gaussian distribution, this paper proposesRC(M) regression models to decompose the residual associations between the polytomous variables. Based on Goodman's (1979, 1985)RC(M) association model, a distinctive feature ofRC(M) regression models is that they facilitate the joint estimation of effects due to manifest and omitted (continuous) variables
without requiring numerical integration. TheRC(M) regression models are illustrated using data from the High School and Beyond study (Tatsuoka & Lohnes, 1988).
This article was accepted for publication, when Willem J. Heiser was the Editor ofPsychometrika. This research was supported by grants from the National Science Foundation (#SBR96-17510 and #SBR94-09531) and the Bureau
of Educational Research at the University of Illinois. We thank Jee-Seon Kim for comments and computational assistance. 相似文献
467.
Bruce Bloxom 《Psychometrika》1985,50(3):301-321
A constrained quadratic spline is proposed as an estimator of the hazard function of a random variable. A maximum penalized likelihood procedure is used to fit the estimator to a sample of psychological response times. The results of a small simulation study suggest that, with a sample size of 500, the procedure may provide a reasonably precise estimate of the shape of a hazard function.This research was conducted under the auspices of the Naval Postgraduate School during the author's sabbatical from Vanderbilt University and was partially supported by the Navy Personnal Research and Development Center. The author wishes to thank Jules Borack, Richard Sorenson, and two anonymous reviewers for a number of useful and stimulating comments on the work reported here. Thanks are also due to David Kohfeld for providing the data which were used in the empirical example. 相似文献
468.
Consumption-leisure tradeoffs in pigeons: Effects of changing marginal wage rates by varying amount of reinforcement 下载免费PDF全文
Pigeons' rates of responding and food reinforcement under simple random-ratio schedules were compared with those obtained under comparable ratio schedules in which free food deliveries were added, but the duration of each food delivery was halved. These ratio-with-free-food schedules were constructed so that, were the pigeon to maintain the same rate of responding as it had under the simple ratio schedule, total food obtained (earned plus free) would remain unchanged. However, any reduction in responding would reduce total food consumption below that under the simple ratio schedule. These “compensated wage decreases” led to decreases in responding and decreases in food consumption, as predicted by an economic model of labor supply. Moreover, the reductions in responding increased as the ratio value increased (i.e., as wage rates decreased). Pigeons, therefore, substituted leisure for consumption. The relationship between these procedures and negative-income-tax programs is noted. 相似文献
469.
It is shown that the scoring algorithm for maximum likelihood estimation in exploratory factor analysis can be developed in a way that is many times more efficient than a direct development based on information matrices and score vectors. The algorithm offers a simple alternative to current algorithms and when used in one-step mode provides the simplest and fastest method presently available for moving from consistent to efficient estimates. Perhaps of greater importance is its potential for extension to the confirmatory model. The algorithm is developed as a Gauss-Newton algorithm to facilitate its application to generalized least squares and to maximum likelihood estimation.This research was supported by NSF Grant MCS-8301587. 相似文献
470.
Staddon JE 《Journal of the experimental analysis of behavior》1988,49(2):303-320
There is continuing controversy about the behavioral process or processes that underlie the major regularities of free-operant choice such as molar matching and systematic deviations therefrom. A recent interchange between Vaughan and Silberberg and Ziriax concerned the relative merits of melioration, and a computer simulation of molecular maximizing. There are difficulties in evaluating theories expressed as computer programs because many arbitrary decisions must often be made in order to get the programs to operate. I therefore propose an alternative form of model that I term quasi-dynamic as a useful intermediate form of theory appropriate to our current state of knowledge about free-operant choice. Quasi-dynamic models resemble the game-theoretic analyses now commonplace in biology in that they can predict stable and unstable equilibria but not dynamic properties such as learning curves. It is possible to interpret melioration as a quasi-dynamic model. An alternative quasi-dynamic model for probabilistic choice, ratio invariance, has been proposed by Horner and Staddon. The present paper compares the predictions of melioration and ratio invariance for five experimental situations: concurrent variable-interval variable-interval schedules, concurrent variable-interval variable-ratio schedules, the two-armed bandit (concurrent random-ratio schedules), and two types of frequency-dependent schedule. Neither approach easily explains all the data, but ratio invariance seems to provide a better picture of pigeons' response to probabilistic choice procedures. Ratio invariance is also more adaptive (less susceptible to “traps”) and closer to the original expression of the law of effect than pure hill-climbing processes such as momentary maximizing and melioration, although such processes may come in to play on more complex procedures that provide opportunities for temporal discrimination. 相似文献