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91.
Despite skepticism on the part of the health care delivery system, increasing numbers of women and couples are relying on natural family planning methods to avoid or achieve pregnancy. Most clients require 2-4 cycles to become familiar with the delineation of the fertile phase. Both the ovulation and the sympto-thermal methods are considered to have a method effectiveness of at least 98%. Teaching-related unplanned pregnancies fall below 5%. Use of the Billings ovulation method requires the couple to abstain from intercourse from the beginning of mucus until the 4th day after peak. The sympto-thermal method is preferred by those desiring a multiple-index approach. 75-80% of users of this method can detect cervical softening and dilatation, and 50% are aware of the change of position of the cervix. Knowledge of mucus buildup patterns can be expecially important for adolescents, lactating women, and premenopausal women in helping them to determine whether cycles are ovulatory. Instruction in interpretation of the mucus cycle is further advised in cases of infertility. Unwillingness of the partners to practice it constitutes the only contraindication to natural family planning. However, couples are advised to wait for the postovulatory infertile phase of the cycle to have intercourse in cases where prgnancy would pose a serious threat to the life of the mother or fetus. Although some groups recommend the use of a barrier method rather than abstinence during fertile periods, this practice makes mucus recognition more difficult and impedes confidence in the method. Attainment of couple autonomy in natural family planning involves 2 phases: 1) correct recognition of the signs of fertility and 2) comfort with periodic asbsinence. Successful autonomy is reflected in the high continuation rates found in programs that offer adequate counseling support.  相似文献   
92.
We report an experiment on two treatments of an ultimatum minigame. In one treatment, responders reactions are hidden to proposers. We observe high rejection rates reflecting responders intrinsic resistance to unfairness. In the second treatment, proposers are informed, allowing for dynamic effects over eight rounds of play. The higher rejection rates can be attributed to responders provision of a public good: Punishment creates a group reputation for being tough and effectively educate proposers. Since rejection rates with informed proposers drop to the level of the treatment with non-informed proposers, the hypothesis of responders enjoyment of overt punishment is not supported.  相似文献   
93.
The t distribution has proved to be a useful alternative to the normal distribution especially When robust estimation is desired. We consider the multivariate nonlinear Student-t regression model and show that the biased of the estimates of the regression coefficients can be computed from an auxiliary generalized linear regression. We give a formula for the biases of the estimates of the parameters in the scale matrix, which also can be computed by means of a generalized linear regression. We briefly discuss some important special cases and present simulation results which indicate that our bias-corrected estimates outperform the uncorrected ones in small samples.  相似文献   
94.
The purpose of the paper is to provide a general framework for analyzing “preference for opportunities.” Based on two simple axioms a fundamental result due to Kreps is used in order to represent rankings of opportunity sets in terms of multiple preferences. The paper provides several refinements of the basic representation theorem. In particular, a condition of “closedness under compromise” is suggested in order to distinguish the flexibility interpretation of the model from normative interpretations which play a crucial role in justifying the intrinsic value of opportunities. Moreover, the paper clarifies the link between the multiple preference approach and the “choice function” approach to evaluating opportunities. In particular, it is shown how the well-known Aizerman/Malishevski result on rationalizability of choice functions can be obtained as a corollary from the more general multiple preference representation of a ranking of opportunity sets. Received: 3 September 1996 / Accepted: 18 August 1997  相似文献   
95.
We study the dividend policy of firms in regulated network industries, focusing on the impact of different regulatory regimes and government control. We link payout and smoothing decisions to different regulatory mechanisms (cost‐based vs. incentive regulation) and state versus private ownership. We test our predictions on a panel of listed European electric utilities, accounting for potential endogeneity of the choice of regulatory and ownership patterns. We find that incentive‐regulated firms smooth their dividends less than cost‐based regulated firms and that they report higher target payout ratios. Consistent with the interest group theory of regulation, we find that incentive regulation schemes are less likely when the state is still an important shareholder in the sector. Additionally, our results show that government control undermines the efficiency‐enhancing effects of incentive regulation on dividend policy, for example, lower smoothing is only due to private firms. (JEL G35, L51, L32, L9)  相似文献   
96.
Aiming at a more comprehensive assessment of nonverbal vocal emotion communication, this article presents the development and validation of a new rating instrument for the assessment of perceived voice and speech features. In two studies, using two different sets of emotion portrayals by German and French actors, ratings of perceived voice and speech characteristics (loudness, pitch, intonation, sharpness, articulation, roughness, instability, and speech rate) were obtained from non-expert (untrained) listeners. In addition, standard acoustic parameters were extracted from the voice samples. Overall, highly similar patterns of results were found in both studies. Rater agreement (reliability) reached highly satisfactory levels for most features. Multiple discriminant analysis results reveal that both perceived vocal features and acoustic parameters allow a high degree of differentiation of the actor-portrayed emotions. Positive emotions can be classified with a higher hit rate on the basis of perceived vocal features, confirming suggestions in the literature that it is difficult to find acoustic valence indicators. The results show that the suggested scales (Geneva Voice Perception Scales) can be reliably measured and make a substantial contribution to a more comprehensive assessment of the process of emotion inferences from vocal expression.  相似文献   
97.
Invited article: Face,voice, and body in detecting deceit   总被引:1,自引:0,他引:1  
Studies based on mean accuracy of a group of subjects suggest that most observers do no better than chance in detecting the lies of others. We argue that a case-by-case methodology, like that used in polygraphy studies may be more useful. Three behavioral measures (two kinds of smiles and pitch) were used to make predictions about the lying or truthfulness of each of 31 subjects. A case-by-case analysis of the hits and misses achieved in this way yielded an over-all accuracy of 86%. The effect on lie detection accuracy of individual differences in the use and control of different behavioral channels is discussed.Paul Ekman's work is supported by a Research Scientist Award from the National Institute of Mental Health (MH 06092).  相似文献   
98.
A robust Bayesian analysis in a conjugate normal framework for the simple ANOVA model is suggested. By fixing the prior mean and varying the prior covariance matrix over a restricted class, we obtain the so-called HiFi and core region, a union and intersection of HPD regions. Based on these robust HPD regions we develop the concept of a ‘robust Bayesian judgement’ procedure. We apply this approach to the simple analysis of variance model with orthogonal designs. The example analyses the costs of an asthma medication obtained by a two-way cross-over study.  相似文献   
99.
The purpose of the study was to identify physical activity questionnaires for older adults that might be suitable outcome measures in clinical trials of fall-injury-prevention intervention and to undertake a systematic quality assessment of their measurement properties. PubMed, CINAHL, and PsycINFO were systematically searched to identify measurements and articles reporting the methodological quality of relevant measures. Quality extraction relating to content, population, reliability, validity, responsiveness, acceptability, practicality, and feasibility was undertaken. Twelve outcome measures met the inclusion criteria. There is limited evidence about the measures' properties. None of the measures is entirely satisfactory for use in a large-scale trial at present. There is a need to develop suitable measures. The Stanford 7-day Physical Activity Recall Questionnaire and the Community Health Activities Model Program for Seniors questionnaire might be appropriate for further development. The results have implications for the designs of large-scale trials investigating many different geriatric syndromes.  相似文献   
100.
The facial behavior during a marble rolling game was analyzed for two samples of children between the ages of 2 and 5 years using the Facial Action Coding System (FACS). In addition, for a subsample of children temperament ratings were available. Analysis of coding reliability showed that frequency as well as temporal location coding can be reliably performed for preschoolers. The facial movements show a frequency distribution which is highly similar in both samples. Movements of the mouth, especially the components of smiling, and some movements of the eye region, were observed frequently. Most other facial movements were infrequent events. The more often shown facial movements were stable over a period up to 18 months. In addition, sum-scores of emotion-relevant Action Units were meaningfully related to infant temperament characteristics.  相似文献   
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