全文获取类型
收费全文 | 54410篇 |
免费 | 1424篇 |
国内免费 | 19篇 |
出版年
2020年 | 428篇 |
2019年 | 531篇 |
2018年 | 4039篇 |
2017年 | 3361篇 |
2016年 | 2933篇 |
2015年 | 760篇 |
2014年 | 762篇 |
2013年 | 3238篇 |
2012年 | 1741篇 |
2011年 | 3508篇 |
2010年 | 3206篇 |
2009年 | 2192篇 |
2008年 | 2710篇 |
2007年 | 3187篇 |
2006年 | 1015篇 |
2005年 | 1110篇 |
2004年 | 1068篇 |
2003年 | 954篇 |
2002年 | 924篇 |
2001年 | 986篇 |
2000年 | 971篇 |
1999年 | 753篇 |
1998年 | 455篇 |
1997年 | 383篇 |
1996年 | 358篇 |
1995年 | 363篇 |
1994年 | 340篇 |
1993年 | 318篇 |
1992年 | 589篇 |
1991年 | 596篇 |
1990年 | 563篇 |
1989年 | 527篇 |
1988年 | 548篇 |
1987年 | 504篇 |
1986年 | 493篇 |
1985年 | 513篇 |
1984年 | 435篇 |
1983年 | 385篇 |
1982年 | 340篇 |
1981年 | 347篇 |
1979年 | 473篇 |
1978年 | 382篇 |
1977年 | 321篇 |
1975年 | 366篇 |
1974年 | 450篇 |
1973年 | 445篇 |
1972年 | 336篇 |
1971年 | 335篇 |
1968年 | 389篇 |
1967年 | 337篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
971.
Nonparametric regression techniques, which estimate functions directly from noisy data rather than relying on specific parametric models, now play a central role in statistical analysis. We can improve the efficiency and other aspects of a nonparametric curve estimate by using prior knowledge about general features of the curve in the smoothing process. Spline smoothing is extended in this paper to express this prior knowledge in the form of a linear differential operator that annihilates a specified parametric model for the data. Roughness in the fitted function is defined in terms of the integrated square of this operator applied to the fitted function. A fastO(n) algorithm is outlined for this smart smoothing process. Illustrations are provided of where this technique proves useful. 相似文献
972.
Schneider Barbara Swanson Christopher B. Riegle-Crumb Catherine 《Social Psychology of Education》1997,2(1):25-53
Course sequences are strands of courses in particular content areas that span a student's educational career. Courses that are differentiated and sequentially organized, such as mathematics and science course sequences, create opportunities for positional advantages in a school's curricular structure. When students make a nonroutine change of schools – that is, transferring to a school outside of the regular attendance zone – they are at risk of changing their positional advantage. Using data from the National Education Longitudinal Study of 1988–94 (NELS:88–94), we examine the educational outcomes of sequences and explore curricular dislocations within the context of school choice. We find that the strongest predictors of 12th-grade mathematics and science course sequences are a student's course sequences at 10th grade. With regard to outcomes, students in higher mathematics and science sequences show greater achievement gains. Furthermore, students in higher mathematics sequences are less likely to have behavior problems and are more likely to graduate from high school and attend college. Students who make a nonroutine change of schools are more likely to be in lower course sequences than students who do not transfer. Thus, course sequences in mathematics and science are tangible experiences with real consequences for students' lives during and beyond high school and are sensitive to transitions which disrupt the continuity of students' high school careers. 相似文献
973.
In this paper, we report an original study of the relationships between self-attributed need for uniqueness and several consumer dispositions. The results indicate that the self-attributed need for uniqueness is related to consumers' desires for scarce, innovative, and customized products and to consumers' preferences for unusual shopping venues, but not to consumers' susceptibilities to normative influence. Moreover, we find that these relationships are mediated by a latent variable reflecting individual differences in the tendency to pursue uniqueness through consumption. The theoretical and practical implications of these results are discussed along with directions for future research. 相似文献
974.
To be competitive in today's job market, many entry-level management candidates are looking to electronic technology to help them find employment. Although technology is an essential part of today's business environment, the findings of this study indicate that very few of the human resource/personnel directors (HR/PD) in the top 100 privately owned companies in Georgia are using electronic technology to fill entry-level managerial positions. These HR/PD, however, view positively those applicants who use electronic methods for job searching and predict that these methods will become a common practice within 2 years. 相似文献
975.
STEPHEN B. FORTSON 《Journal of Employment Counseling》1997,34(3):104-107
African American men suffer one of the highest attrition rates of any racial or gender group in college. This study evaluated a retention program designed to increase academic self-concept by engaging participants in a 10-week course that taught career planning, cultural awareness, job interviewing and resume writing skills, and academic responsibility. The results of the analysis suggest that the course had no effect on academic self-concept. 相似文献
976.
Robert W. Holt Jennifer A. O'Connor Jennifer L. Smith Theodore L. Gessner Timothy C. Clifton Michael D. Mumford 《Journal of applied social psychology》1997,27(9):781-799
This study examined the effects of information about a landlord's personality on juror judgments for a landlord-tenant civil trial. The personality information manipulated was specifically relevant to destructive acts. Alternative versions of witness testimony were used to describe a landlord either high or low on need for power. treating people as objects, and negative life themes. This information strongly influenced aspects of the schema for this case constructed by the individual mock jurors. Destructive personality information caused dislike of the landlord and lowered the credibility of his story. If the landlord treated people as objects, the credibility of the tenant's story and positive evaluations of the tenant increased. Juror judgments about relative fault were strongly shifted by destructive personality information. An empirical model for juror decisions indicated a dynamic interplay of story components and fault judgments. 相似文献
977.
Michael McCall 《Journal of applied social psychology》1997,27(5):453-462
This research examined whether previously documented social benefits associated with physical attractiveness would influence the decision to request proof of legal age for the purchase of alcohol. Undergraduates were presented with a photograph of a highly attractive or less attractive member of the opposite gender that they diddid not expect to meet. Results indicated that the opportunity to interact with a highly attractive member of the opposite gender significantly reduced the chances that the target would be asked to provide proof of legal age. Physical attractiveness was positively related to perceptions of age in the perception of male targets, hut not for females. The implications of these findings for restricting alcohol availability among minors are considered. 相似文献
978.
979.
Current status of the Rorschach Inkblot Method 总被引:1,自引:0,他引:1
Weiner IB 《Journal of personality assessment》1997,68(1):5-19
The current scientific, clinical, and professional status of the Rorschach Inkblot Method (RIM) is reviewed with respect to its psychometric properties, the applied purposes it can be expected to serve, the extent of its use, and the nature of prevailing attitudes toward it. Available evidence indicates that the RIM is a psychometrically sound measuring instrument that provides valid assessments of personality characteristics and can facilitate differential diagnosis and treatment planning and evaluation. The RIM continues as in the past to be widely used by both clinicians and researchers. However, the esteem in which it is held by practitioners, who are generally agreed that clinical psychologists should be competent in Rorschach assessment, is not universally shared by academicians, many of whom presently question the future place of Rorschach training in graduate education. 相似文献
980.
Nicole B. Barenbaum 《Journal of personality》1997,65(3):743-755
ABSTRACT Gordon Allport has frequently been criticized for advocating the use of idiographic studies but undertaking only one such study himself. This article describes Allport's work on the case of Marion Taylor, an unpublished study that clearly contributed to his later work on the case method. The unfinished Taylor case materials suggest that Ada Allport was an important collaborator in Allport's work with individual cases. The case of Taylor is compared with the later case of Jenny Masterson using Allport's rules for the preparation of case studies in order to shed light on Allport's ambivalence regarding case studies. 相似文献