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31.
Recent studies of old-age mortality trends assess whether longevity improvements over time are linked to increasing compression of mortality at advanced ages. The historical backdrop of these studies is the long-term improvement in a population's socioeconomic resources that fueled longevity gains. We extend this line of inquiry by examining whether socioeconomic differences in longevity within a population are accompanied by old-age mortality compression. Specifically, we document educational differences in longevity and mortality compression for older men and women in the United States. Drawing on the fundamental cause of disease framework, we hypothesize that both longevity and compression increase with higher levels of education and that women with the highest levels of education will exhibit the greatest degree of longevity and compression. Results based on the Health and Retirement Study and the National Health Interview Survey Linked Mortality File confirm a strong educational gradient in both longevity and mortality compression. We also find that mortality is more compressed within educational groups among women than men. The results suggest that educational attainment in the United States maximizes life chances by delaying the biological aging process.  相似文献   
32.
The developmental period of adolescence is characterized by increasing incidence of health risk behaviors (HRBs). Based on theoretical models that emphasize the moderating role of cognitive control, this study examined how neural correlates of cognitive control and risk sensitivity interact to predict HRBs among late adolescents (17–20 years). Neuroimaging data indicate that risk‐related hemodynamic activity in the anterior insula during anticipation of uncertain outcomes predicts HRBs among late adolescents exhibiting greater dorsal anterior cingulate cortex (dACC) activity during a cognitive interference task but not among late adolescents requiring less dACC activity. These results present neural evidence for a significant moderating effect of cognitive control on the link between risk sensitivity and HRBs among late adolescents.  相似文献   
33.
Although a previous study found that neural network forecasts were more accurate than time series models for predicting Latin American stock indexes, the forecasting accuracy of neural network for predicting gold futures prices has never been discussed. Therefore, the first objective of this study is to compare the forecasting accuracy of a neural network model with that of ARIMA models. Furthermore, the fluctuations in gold futures are not only influenced by the quantitative variables, but also by many nonquantifiable factors, such as wars, international relations, and terrorist attacks. The second objective of this study is therefore to propose the integration of text mining and an artificial neural network to forecast gold futures prices. The historical gold futures prices from 1999 to 2008 were used as training data and testing data, and the prices of 2009 were used to examine the effectiveness of the proposed model. The results of empirical analysis showed that an artificial neural network forecasted gold futures prices better than ARIMA models did. In addition, text mining provided a reasonable explanation of the trend in gold futures prices.  相似文献   
34.
A cross-sectional study was conducted to explore the prevalence and severity of health-related complaints perceived by adult males of Hong Kong by using the Hong Kong Traditional Chinese versions of the Aging males’ symptoms (AMS) scale and the 5-dimensional and 3-level European Quality of life (EQ-5D-3L) questionnaire. A total of 825 adult males aged 40 years or above were surveyed, and observed that 80% of the population was living with little-to-mild levels of aging symptoms with mean total scores ranged between 26.02?±?7.91 and 32.99?±?7.91 in different age groups. Such symptoms were correlated with age, especially for the somato-vegetative and sexual symptoms. The most severe AMS symptoms were observed in the oldest age group at 70 years or above, with 76%, 34% and 70% living with moderate-to-severe levels of somato-vegetative, psychological and sexual symptoms, respectively. The result was highly correlated with the EQ-5D-3L questionnaire. Secondly, the Hong Kong Aging males’ symptoms (AMS) scale was shown to have good reliability with test–retest coefficient at 0.79 (ranged 0.66–0.87) and Cronbach’s alpha coefficient at 0.88 (ranged 0.70–0.84). In summary, the population of Hong Kong male adults was commonly living with little-to-mild levels of aging symptoms, whereas their severity was correlated with age.  相似文献   
35.
This paper gives a two-sample procedure for selecting the m populations with the largest means from k normal populations with unknown variances. The method is a generalization of a recent work by Ofosu [1973] and hence should find wider practical applications. The experimenter takes an initial sample of preset size N0 from each population and computes an unbiased estimate of its variance. From this estimate he determines the second sample size for the population according to a table presented for this purpose. The populations associated with the m largest overall sample means will be selected. The procedure is shown to satisfy a confidence requirement similar to that of Ofosu.  相似文献   
36.
Subgroup analyses are a routine part of clinical trials to investigate whether treatment effects are homogeneous across the study population. Graphical approaches play a key role in subgroup analyses to visualise effect sizes of subgroups, to aid the identification of groups that respond differentially, and to communicate the results to a wider audience. Many existing approaches do not capture the core information and are prone to lead to a misinterpretation of the subgroup effects. In this work, we critically appraise existing visualisation techniques, propose useful extensions to increase their utility and attempt to develop an effective visualisation approach. We focus on forest plots, UpSet plots, Galbraith plots, subpopulation treatment effect pattern plot, and contour plots, and comment on other approaches whose utility is more limited. We illustrate the methods using data from a prostate cancer study.  相似文献   
37.
Due to recent policy changes in the USA and Taiwan, Taiwanese immigrants residing in the USA face a choice of continuing to receive health care in the USA or returning to Taiwan for treatment care. This study uses a quantitative survey to explore the association between recent health policy changes and the health care choice of Taiwanese immigrants residing in the USA. These findings indicate that there are statistically significant associations between a variety of factors and the Taiwanese immigrants' desire to return to Taiwan for health care under the new national health insurance plan (2nd NHIA). The variables positively associated with a desire to return to Taiwan for health care include the length of domicile and residence required to receive benefits, a nostalgic desire to return to Taiwan, the lower cost of health care in Taiwan, and if the respondents had come to the USA before 1996. The negatively associated variables include having a job in the USA, having a desire to return to Taiwan to live after retirement, the language preference in communications with a doctor, and a preference about the best place to receive dental treatment. The study reveals the dynamics behind the health care decision‐making of Taiwanese immigrants and particularly their choice of whether to seek care in the USA or in Taiwan.  相似文献   
38.
我国古代文学理论批评中,有一个独特的现象,就是以"味"论诗.而以味论词,则始于金代元好问.元氏在<遗山自题乐府>中举出黄庭坚的<渔夫词>和陈与义的两首<临江仙>,作为有味词的代表作.这三首词经过详细分析后,就不难看出元氏所谓"词味",指的是含蓄委婉地包含在词中的深层意思,要细心玩味才能理解.  相似文献   
39.
40.
Abstract

Objective: This study tested the interactive relationships between college students’ perceived capability of regulating negative emotions and savoring positive emotions on mental health outcomes, including anxiety and depressive symptoms. Participants: Participants were healthy undergraduates (n?=?167) recruited from two universities in Hong Kong. Methods: Students completed four scales assessing their perceived capability of using strategies to regulate negative and positive emotions and their anxiety and depressive symptoms. Results: Findings revealed that both anxiety and depressive symptoms were negatively linked to perceived capabilities of regulating negative emotions and savoring positive emotions. Furthermore, regulating negative emotions interacted with savoring positive emotions to predict anxiety symptoms. Conclusions: The need to simultaneously perform negative and positive emotion regulation is highlighted. The results suggest the priority of regulating negative emotions over savoring positive emotions in alleviating anxiety symptoms. Nevertheless, enhancing positive emotion shows greater benefits for those who are less adept at regulating negative emotions.  相似文献   
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