全文获取类型
收费全文 | 4956篇 |
免费 | 267篇 |
国内免费 | 1篇 |
专业分类
5224篇 |
出版年
2023年 | 65篇 |
2022年 | 77篇 |
2021年 | 109篇 |
2020年 | 149篇 |
2019年 | 141篇 |
2018年 | 240篇 |
2017年 | 248篇 |
2016年 | 220篇 |
2015年 | 132篇 |
2014年 | 174篇 |
2013年 | 729篇 |
2012年 | 369篇 |
2011年 | 351篇 |
2010年 | 204篇 |
2009年 | 135篇 |
2008年 | 300篇 |
2007年 | 251篇 |
2006年 | 214篇 |
2005年 | 138篇 |
2004年 | 116篇 |
2003年 | 112篇 |
2002年 | 103篇 |
2001年 | 42篇 |
2000年 | 73篇 |
1999年 | 50篇 |
1998年 | 40篇 |
1997年 | 27篇 |
1996年 | 28篇 |
1995年 | 21篇 |
1994年 | 32篇 |
1993年 | 20篇 |
1992年 | 16篇 |
1991年 | 36篇 |
1990年 | 16篇 |
1989年 | 24篇 |
1988年 | 17篇 |
1987年 | 16篇 |
1986年 | 13篇 |
1985年 | 16篇 |
1984年 | 14篇 |
1983年 | 8篇 |
1982年 | 9篇 |
1981年 | 11篇 |
1980年 | 10篇 |
1979年 | 10篇 |
1975年 | 7篇 |
1971年 | 8篇 |
1968年 | 10篇 |
1966年 | 8篇 |
1965年 | 8篇 |
排序方式: 共有5224条查询结果,搜索用时 0 毫秒
931.
The Type I error rates and powers of three recent tests for analyzing nonorthogonal factorial designs under departures from the assumptions of homogeneity and normality were evaluated using Monte Carlo simulation. Specifically, this work compared the performance of the modified Brown-Forsythe procedure, the generalization of Box's method proposed by Brunner, Dette, and Munk, and the mixed-model procedure adjusted by the Kenward-Roger solution available in the SAS statistical package. With regard to robustness, the three approaches adequately controlled Type I error when the data were generated from symmetric distributions; however, this study's results indicate that, when the data were extracted from asymmetric distributions, the modified Brown-Forsythe approach controlled the Type I error slightly better than the other procedures. With regard to sensitivity, the higher power rates were obtained when the analyses were done with the MIXED procedure of the SAS program. Furthermore, results also identified that, when the data were generated from symmetric distributions, little power was sacrificed by using the generalization of Box's method in place of the modified Brown-Forsythe procedure. 相似文献
932.
This paper analyzes the sum score based (SSB) formulation of the Rasch model, where items and sum scores of persons are considered
as factors in a logit model. After reviewing the evolution leading to the equality between their maximum likelihood estimates,
the SSB model is then discussed from the point of view of pseudo-likelihood and of misspecified models. This is then employed
to provide new insights into the origin of the known inconsistency of the difficulty parameter estimates in the Rasch model.
The main results consist of exact relationships between the estimated standard errors for both models; and, for the ability
parameters, an upper bound for the estimated standard errors of the Rasch model in terms of those for the SSB model, which
are more easily available.
The authors acknowledge partial financial support from the FONDECYT Project No. 1060722 from the Chilean Government, and the
BIL05/03 grant to P. De Boeck, E. Lesaffre and G. Molenberghs (Flanders) for a collaboration with G. del Pino, E. San Martín,
F. Quintana and J. Manzi (Chile). 相似文献
933.
The Assumption of Proportional Components when Candecomp is Applied to Symmetric Matrices in the Context of Indscal 总被引:2,自引:0,他引:2
The use of Candecomp to fit scalar products in the context of INDSCAL is based on the assumption that the symmetry of the
data matrices involved causes the component matrices to be equal when Candecomp converges. Ten Berge and Kiers gave examples
where this assumption is violated for Gramian data matrices. These examples are believed to be local minima. It is now shown
that, in the single-component case, the assumption can only be violated at saddle points. Chances of Candecomp converging
to a saddle point are small but still nonzero. 相似文献
934.
Ferran Casas Germà Coenders Robert A. Cummins Mònica González Cristina Figuer Sara Malo 《Journal of Happiness Studies》2008,9(2):197-205
The relationship between the subjective well-being of parents and their own 12–16-year-old children was explored in a Spanish
sample of N = 266 families. A positive relationship was expected due to both a shared environment and the possibility of the genetic
transmission of subjective well-being ‘set-points’. A positive significant relationship was found for the summated scale of
satisfaction domains forming the Personal Well-being Index, and for the specific domains of health and security for the future.
However, no relationship was found for the other five domains that make up this Index or for satisfaction with life as a whole.
We conclude while these results provide some evidence for the expected influence of a shared environment, they have failed
to provide evidence for high heritability of set-points for subjective well-being. 相似文献
935.
This article examines the importance of semantic processes in the recognition of emotional expressions, through a series of three studies on false recognition. The first study found a high frequency of false recognition of prototypical expressions of emotion when participants viewed slides and video clips of nonprototypical fearful and happy expressions. The second study tested whether semantic processes caused false recognition. The authors found that participants made significantly higher error rates when asked to detect expressions that corresponded to semantic labels than when asked to detect visual stimuli. Finally, given that previous research reported that false memories are less prevalent in younger children, the third study tested whether false recognition of prototypical expressions increased with age. The authors found that 67% of eight- to nine-year-old children reported nonpresent prototypical expressions of fear in a fearful context, but only 40% of 6- to 7-year-old children did so. Taken together, these three studies demonstrate the importance of semantic processes in the detection and categorization of prototypical emotional expressions. 相似文献
936.
Emotional-neutral pairs of visual scenes were presented peripherally (with their inner edges 5.2 degrees away from fixation) as primes for 150 to 900 ms, followed by a centrally presented recognition probe scene, which was either identical in specific content to one of the primes or related in general content and affective valence. Results indicated that (a) if no foveal fixations on the primes were allowed, the false alarm rate for emotional probes was increased; (b) hit rate and sensitivity (A') were higher for emotional than for neutral probes only when a fixation was possible on only one prime; and (c) emotional scenes were more likely to attract the first fixation than neutral scenes. It is concluded that the specific content of emotional or neutral scenes is not processed in peripheral vision. Nevertheless, a coarse impression of emotional scenes may be extracted, which then leads to selective attentional orienting or--in the absence of overt attention--causes false alarms for related probes. 相似文献
937.
External validation of the computerized, group administrable adaptation of the “operation span task”
One of the most widely used tasks for measuring working memory capacity is the operation span task (OSPAN; Turner & Engle, 1989). This task has almost always been applied individually, and stimuli presentation is controlled by the experimenter. Recently, De Neys, d'Ydewalle, Schaeken, and Vos (2002) improved the administration procedure by designing an automated, group-administrable version of the task (GOSPAN). They found GOSPAN to be reliable, and they also provided evidence on its validity (a significant positive correlation between GOSPAN and OSPAN scores). However, an external test of GOSPAN validity is still lacking. In this work, we present such a validation for the automated version, when the task is administered both individually (Experiment 1) and to groups (Experiment 2). There are abundant previous data on the relation between working memory capacity and reading comprehension. In this work, this relation is studied using an automated OSPAN version to measure working memory capacity. Given that our results are similar to those found using the original OSPAN, our data support the external validity of the automated version of the task. We also tested the reliability of the task and found high internal consistency in both experiments. 相似文献
938.
Concepcin Fernndez‐Villanueva Roberto Domínguez‐Bilbao Juan Carlos Revilla‐Castro Amy Anagnostou 《Aggressive behavior》2006,32(2):137-145
A quantitative analysis of broadcasted violence by the main television (TV) channels transmitting for Madrid (Spain) was carried out using a novel method that randomly selects fragments of delimited duration from TV broadcasts. The device selects acts of aggression shown in those TV extracts, and classifies them according to their type. There was a high incidence of aggressive acts, especially physical (particularly leading to death), in TV fiction: films, serials and promos. The device also allowed examination of the prominence of aggression in children's programs, as well as showing minimal variation in the number of aggressive acts over screened time intervals. The pattern of the collected data suggests that the broadcasting of violence on TV emphasizes the conflicting elements of social reality, reproducing it in fiction, news reports and children's shows. Aggr. Behav. 32:137–145. 2006. © 2006 Wiley‐Liss, Inc. 相似文献
939.
Guido Van Steendam Guido Van Steendam András Dinnyés Jacques Mallet Rolando Meloni Carlos Romeo Casabona Jorge Guerra González Josef Kuře Eörs Szathmáry Jan Vorstenbosch Péter Molnár David Edbrooke Judit Sándor Ferenc Oberfrank Ron Cole-Turner István Hargittai Beate Littig Miltos Ladikas Emilio Mordini Hans E. Roosendaal Maurizio Salvi Balázs Gulyás Diana Malpede 《Science and engineering ethics》2006,12(3):415-420
940.