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241.
In comparing open and closed economies, researchers often arrange shorter sessions under the former condition than under the latter. Several studies indicate that session length per se can affect performance and there are some data that indicate that this variable can influence demand functions. To provide further data, the present study exposed domestic hens to series of increasing fixed-ratio schedules with the length of the open-economy sessions varied over 10, 40, 60, and 120 min. Session time affected the total-session response rates and pause lengths. The shortest session gave the greatest response rates and shortest pauses and the longest gave the lowest response rates and longest pauses. The total-session demand functions also changed with session length: The shortest session gave steeper initial slopes (i.e., the functions were more elastic at small ratios) and smaller rates of change of elasticity than the longest session. Response rates, pauses, and demand functions were, however, similar for equivalent periods of responding taken from within sessions of different overall lengths (e.g., total-session data for 10-min sessions and the data for the first 10 min of 120-min sessions). These findings suggest that differences in session length can confound the results of studies comparing open and closed economies when those economies are arranged in sessions that differ substantially in length, hence data for equivalent-length periods of responding, rather than total-session data, should be of primary interest under these conditions. 相似文献
242.
Kobe Millet 《Personality and individual differences》2011,51(4):397-401
The present paper gives an overview of recent research on the association between 2D:4D and different types of economic behavior. Particular attention is given to the importance of context dependence of relationships between 2D:4D and economic as well as other, social, behavior. Patterns of results are discussed from the perspective that 2D:4D might serve as a biological marker of dispositional dominance. This overview hopes to stimulate research from an interactionist perspective which focuses at relationships between 2D:4D and behavior that only appear when specific situational pressures interact with individual differences in 2D:4D. 相似文献
243.
Mean comparisons are of great importance in the application of statistics. Procedures for mean comparison with manifest variables
have been well studied. However, few rigorous studies have been conducted on mean comparisons with latent variables, although
the methodology has been widely used and documented. This paper studies the commonly used statistics in latent variable mean
modeling and compares them with parallel manifest variable statistics. Our results indicate that, under certain conditions,
the likelihood ratio and Wald statistics used for latent mean comparisons do not always have greater power than the Hotelling
T2 statistics used for manifest mean comparisons. The noncentrality parameter corresponding to the T2 statistic can be much greater than those corresponding to the likelihood ratio and Wald statistics, which we find to be different
from those provided in the literature. Under a fixed alternative hypothesis, our results also indicate that the likelihood
ratio statistic can be stochastically much greater than the corresponding Wald statistic. The robustness property of each
statistic is also explored when the model is misspecified or when data are nonnormally distributed. Recommendations and advice
are provided for the use of each statistic.
The research was supported by NSF grant DMS-0437167 and Grant DA01070 from the National Institute on Drug Abuse.
We would like to thank three referees for suggestions that helped in improving the paper. 相似文献
244.
The second-to-fourth digit ratio (2D:4D) is sexually differentiated and is a likely biomarker for the organisational (permanent) effects of prenatal testosterone on the human brain. Recent research has highlighted a possible role of prenatal testosterone levels in both the etiology of autism-spectrum disorders and in sex and individual differences in cognitive styles of the normal mind (Baron-Cohen’s Extreme Male Brain Theory of Autism and Empathising/Systemising Theory). Importantly, autistic children present lower (hypermasculinised) 2D:4D than healthy controls. Based on these accounts, we investigated the relation of 2D:4D with Baron-Cohen’s measures of empathising (“Reading the Mind in the Eyes” test, RMET; Empathy Quotient, EQ), systemising (Systemising Quotient, SQ), and autistic-like traits (Autism-Spectrum Quotient, AQ) in the general population (N = 423 Austrian adults). Whereas sex differences into the expected direction and of expected size were obtained for all variables and internal scale consistencies tallied to retrievable reference values, 2D:4D was unrelated to RMET, EQ, SQ, and AQ scores. Candidate explanations for this lack of correlation might be possible developmental timing differences in the expression of 2D:4D and empathising/systemising, qualitative (as opposed to quantitative) functional differences between the normal and the autistic mind, or the suboptimal psychometric properties of the measures. 相似文献
245.
246.
本研究探讨同一品类两个强势品牌广告竞争对弱势品牌产生的影响, 研究尝试将广告重复、广告长度作为操控广告竞争强度的具体手段, 运用感知到的广告竞争水平来表示广告竞争强度。研究结果表明, 同一品类两个品牌同时进行广告重复的水平不同, 可以导致被试感知到的广告竞争水平有显著差异, 广告重复次数越多, 被试感知到的广告竞争强度越高, 广告长度对感知到的广告竞争作用不显著。研究同时发现:随着两个强势品牌广告竞争强度的提高, 消费者对弱势品牌的品牌态度降低, 这表明强势品牌广告竞争对弱势品牌具有溢出效应。另外, 研究还发现产品涉入度和产品属性相似性对强势品牌广告竞争的溢出效应具有调节作用, 涉入度低的产品和属性相似性高的产品溢出效应更大。本研究丰富了溢出效应理论, 增加了溢出效应类别, 同时对同一品类内部的广告实践具有重要的指导意义。 相似文献
247.
Edward H. Ip Michelle F. Magee Gretchen A. Youssef Shyh-Huei Chen 《Multivariate behavioral research》2019,54(2):159-172
The Don’t Know (DK) response – taking the form of an omitted response or not-reached at the end of a cognitive test, or explicitly presented as a response option in a social survey – contains important information that is often overlooked. Direct psychometric modeling efforts for DK responses are few and far between. In this article, the linear logistic test model (LLTM) is proposed for delineating the impacts of cognitive operations for a test that contains DK responses. We assume that the DK response is a valid response. The assumption is reasonable for many situations, including low-stakes cognitive tests and attitudinal assessments. By extracting information embedded in the DK response, the method shows how DK can inform the latent construct of interest and the cognitive operations underlying the response to stimuli. Using a proven recoding scheme, the LLTM could be implemented through commonly used programs such as PROC GLIMMIX. Two simulation experiments to evaluate how well the parameters can be recovered were conducted. In addition, two real data examples, from a noncognitive test of health belief assessment and a cognitive test of knowledge in diabetes, are also presented as case studies to illustrate the LLTM for DK response. 相似文献
248.
Peter R. Killeen 《Journal of the experimental analysis of behavior》2019,112(2):111-127
In the accumulation paradigm animals press one manipulandum to accumulate pellets or seconds of access to food, and then press another manipulandum, or run some distance, to collect it. The accumulation may be interpreted as delay discounting, with the animals adjusting the distal amount to compensate for its distance or delay. The amount accumulated before being collected is a linear function of the distance or time that the experimental paradigm stipulates for collecting it. That linear function follows from the Unit‐Price/Unit‐Amount axiom. The inverse of the linear compensation functions gives a delay‐discount hyperbola. The advantages of the accumulation paradigm and analytic framework for delay discounting studies are noted. Compensation functions are then derived from a behavioral regulation model, which generalizes them to contexts where the individual's budget for response cost becomes over‐taxed. In turn, such compensation/regulation models lead directly to representative demand functions. In sum, regulation models provide a theoretical grounding for demand functions, compensation functions, and delay discounting hyperbolas. The parameter that links them is the unit amount k, the slope of the compensation function and of the discount function, the setpoint for consumption in a regulation model, and the ideal quantity consumed at minimal price in a demand analysis. 相似文献
249.
250.
Studies of wheel-running reinforcement: parameters of Herrnstein's (1970) response-strength equation vary with schedule order 下载免费PDF全文
Belke TW 《Journal of the experimental analysis of behavior》2000,73(3):319-331
Six male Wistar rats were exposed to different orders of reinforcement schedules to investigate if estimates from Herrnstein's (1970) single-operant matching law equation would vary systematically with schedule order. Reinforcement schedules were arranged in orders of increasing and decreasing reinforcement rate. Subsequently, all rats were exposed to a single reinforcement schedule within a session to determine within-session changes in responding. For each condition, the operant was lever pressing and the reinforcing consequence was the opportunity to run for 15 s. Estimates of k and R(O) were higher when reinforcement schedules were arranged in order of increasing reinforcement rate. Within a session on a single reinforcement schedule, response rates increased between the beginning and the end of a session. A positive correlation between the difference in parameters between schedule orders and the difference in response rates within a session suggests that the within-session change in response rates may be related to the difference in the asymptotes. These results call into question the validity of parameter estimates from Herrnstein's (1970) equation when reinforcer efficacy changes within a session. 相似文献