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101.
Using the extension of the national PISA 2003 sample (PISA 2003-E) of 15-year-old students, this study analyzes assimilation patterns of immigrants from Turkey, the former USSR, and Poland in terms of educational attainment and performance in mathematics. It explores the extent to which segmented assimilation processes are observed for these groups. Increasing similarity of immigrant students across generations with native students on these dimensions would support the notion of straight-line assimilation, whereas stability in disparities would point to downward assimilation. The results of the study suggest downward assimilation for immigrant students of Turkish descent regarding educational attainment and performance in mathematics. Students whose families immigrated from the former USSR or Poland, in contrast, show patterns of straight-line assimilation. In addition, our analyses suggest that capturing immigrant status as precisely as possible (1.5 generation, intermarriage) is important, as significant differences in educational success and living conditions of these groups would otherwise be overlooked.  相似文献   
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This study applies multilevel logistic regression to Demographic and Health Survey data from 22 sub‐Saharan African countries to examine whether the relationship between child mortality and family structure, with a specific emphasis on polygyny, varies cross‐nationally and over time. Hypotheses were developed on the basis of competing theories on the relationship between child health and family structure. Although children of mothers in polygynous marriages are more likely to die than those of mothers in monogamous unions, the relationship is constant across time. Familial factors including education, socioeconomic status (SES), and urban residence accounted for most of the observed cross‐national variation associated with polygyny. Consequently, improving maternal education and household SES would greatly benefit child health in sub‐Saharan Africa.  相似文献   
105.
We tested group interventions for women with a Turkish migration background living in Austria and suffering from recurrent depression. N = 66 participants were randomized to: (1) Self-Help Groups (SHG), (2) Cognitive Behavior Therapy (CBT) Groups, and (3) a Wait-List (WL) Control condition. Neither SHG nor CBT were superior to WL. On an individual basis, about one third of the participants showed significant improvements with respect to symptoms of depression. Younger women, women with a longer duration of stay in Austria and those who had encountered a higher number of traumatic experiences, showed increased improvement of depressive symptoms. The results suggest that individual treatment by ethnic, female psychotherapists should be preferred to group interventions.  相似文献   
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Occasionally, scientific reports have omitted information on standard deviations, making estimates of effect sizes very difficult to impossible. In such situations, several scholars have recommended obtaining an estimate of the standard deviation of distributions by dividing the range of the distribution (highest value minus lowest value) by four. However, there appears to be little evidence to confirm the validity of this approach. Articles from 2012 to 2015 in the journal Marriage & Family Review were surveyed to find instances where demographic variables (age, education, duration of relationship, number of children) were reported with both standard deviations and ranges. Ratios between range and standard deviations were calculated by several rules of thumb or more complex formulas and compared with the actual ratios obtained. Results indicated that dividing by five in general provided a more accurate estimate of actual standard deviations but accuracy in predicting the true ratio between range and standard deviation was substantially related to the position of the mean score within the range of scores with larger divisors needed as the mean approached either the minimum or the maximum values of the demographic variable (skew). Other recent formulae for estimating the standard deviation were also evaluated, but the skew-based approach appeared to be more accurate than the others. However, further investigation in other samples is needed because the skew-based approach was derived from observation of the data here, which might not replicate in different sets of data.  相似文献   
108.
Hoaglin and Andrews (1975) proposed standards for computational practice and the reporting of computation-based studies. They observed that “statisticians … often pay too little attention to their own principles of design.” To see if the design and reporting had improved, we surveyed five major statistical journals for 1975, 1978, and 1981 to ascertain whether reported simulation studies involved a specified design, justified the choice of the number of iterations, and specified the random number generator(s) used. Eighteen percent of the 1,198 papers surveyed included results based on simulation. We found that 9% of the papers including a simulation study justified the choice of the number of iterations and 44% at least partially specified the random number generator. Hoaglin and Andrews's observation appears still to be true.  相似文献   
109.
The Polya-Eggenberger distribution Involves drawing a ball from an urn containing black and white balls and, after each drawing, returning the ball together with s balls of the same color, The model represents positive contagion since the added balls are the same color as the one drawn, See Johnson and Kotz, (1977),

This paper derives and examines the probability distribution which results from the Polya-Eggenberger model with only one change namely, the s additional balls added after each drawing are of the opposite color, producing a negative contagion model.

Formulas in closed form are presented for the probability distribution function, the mean and variance, all binomial moments and, where s is greater than or equal to the number of balls in the urn at start, the mode, A formula for the mode is conjectured where s is less than the number of balls in the urn at start.

Finally, the probability of obtaining k black balls in n drawings is shown in certain instances to be equal to Ank/n!

where Ank are the Eulerian numbers.  相似文献   
110.
Sexual excitement can be seen as an action disposition. In this study sexual arousal was expected to generate sexual action and to increase interest and responsiveness to sexual stimuli. In two experiments, male and female participants were exposed to a neutral or a sexual film. We measured genital and subjective responses to the film, and sexual behavior following the laboratory visit. In Experiment 2, film exposure was followed by a task in which participants rated the sexual arousability of neutral and sexual pictures. Rating time of the sexual pictures served as an index for sexual interest. Responsiveness to the sexual pictures was measured by modulation of spinal tendinous (T) reflexes. Sexual activity, but not sexual desire, was higher for participants in the sexual film condition than for participants in the neutral condition. Sexual interest and responsiveness to still pictures were not higher for participants in the sexual film condition than for those in the neutral film condition. In addition, men who saw the neutral film showed a greater responsiveness to still pictures than men who saw the sexual film. The results support the view of sexual arousal as an emotional state generating action tendencies and actual sexual behavior.  相似文献   
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