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101.
The importance of eye care in the industry is a first level topic, due to most of the assembly and manufacturing aimed companies of various products that require direct health care of their employees, specially eye care. The lighting system, the lamp features and job tasks are factors that impact over the visual performance of the worker. Each of these factors, either by themselves or in conjunction, influences the visual performance of the employee, and therefore its safety and efficacy. Some of the reported symptoms are: problem of visual fixation, eye redness, tearing, headache, blurred vision, eyelids heaviness and dry eyes, [7]. The research was developed with 48 people, 27 male and 21 female, in the range of ages of 17 to 58 years old. In the experiment were used illumination system base on Diode Emitting lights (LED's) of five different colors (White, Blue, Green, Red and Yellow), the reason of use of LED's it is because are source of monochromatic light, also it is also saving power light and low heating dissipation.  相似文献   
102.
A hierarchical theory of occupational segregation and wage discrimination   总被引:1,自引:0,他引:1  
Becker's model of discrimination is extended to the case where men exhibit distastes for working under female managers. The distribution of women in the resulting occupational hierarchy depends on the number of women in lower occupations, the wages of male workers in lower occupations, and male distastes for female management. Thus, there exists an occupational sorting function, related to wages, that determines the occupational distribution of women. We integrate this sorting function into a standard wage equation to derive a new decomposition of male-female wage differentials and apply it to a sample of insurance industry workers from the 1988 CPS.  相似文献   
103.
In this paper, we propose a Bayesian partition modeling for lifetime data in the presence of a cure fraction by considering a local structure generated by a tessellation which depends on covariates. In this modeling we include information of nominal qualitative variables with more than two categories or ordinal qualitative variables. The proposed modeling is based on a promotion time cure model structure but assuming that the number of competing causes follows a geometric distribution. It is an alternative modeling strategy to the conventional survival regression modeling generally used for modeling lifetime data in the presence of a cure fraction, which models the cure fraction through a (generalized) linear model of the covariates. An advantage of our approach is its ability to capture the effects of covariates in a local structure. The flexibility of having a local structure is crucial to capture local effects and features of the data. The modeling is illustrated on two real melanoma data sets.  相似文献   
104.
To deal with the problem of underestimation of top incomes in household surveys, we propose a methodology to combine the income distributions of the Brazilian 2010 Census (survey) and of 2010 DIRPF (personal income tax reports). The method consists in estimating a system of non-response weights that uses as frame the tax register and is applied to the top of the distribution. After applying this calibration methodology, we decompose inequality income sources. Correcting survey distributions with tax data increases the contribution of non-labor income to inequality, as the case of the Brazilian Census shows. Changes in the methodology do not affect the results substantially.  相似文献   
105.

Aim

To examine foot posture changes during the three trimesters of pregnancy and to determine whether there is a relationship between these changes and the pain experienced in this period.

Methods

The study sample consisted of 62 pregnant women who attended the Gynaecology Service at Hospital ?Santa María del Puerto (Cádiz, Spain), between January 2013 and May 2014. In their first visit, the following sociodemographic and anthropometric data were recorded: age, weight, height and foot size. In addition, information was obtained regarding pain in the lower back, knees, ankles and feet. In this first visit, too, the Foot Posture Index (FPI) was assessed, and three subsequent controls were performed during the first, second and third months of pregnancy (termed Stages 1, 2 and 3, respectively).

Results

In Stage 1, the average foot size (i.e., shoe size) was 38.3 (SD 1.5). This size did not change between Stages 1, 2 and 3. However, body weight and BMI did present statistically significant changes during this period (p < 0.0001). The FPI varied during pregnancy but no relation was observed between these changes and the onset of pain.

Conclusions

During pregnancy, pronation increases but this does not appear to influence the onset of pain in the lower limbs.  相似文献   
106.
In this paper, we develop a flexible cure rate survival model by assuming the number of competing causes of the event of interest to follow the Conway–Maxwell Poisson distribution. This model includes as special cases some of the well-known cure rate models discussed in the literature. Next, we discuss the maximum likelihood estimation of the parameters of this cure rate survival model. Finally, we illustrate the usefulness of this model by applying it to a real cutaneous melanoma data.  相似文献   
107.
It is not uncommon with astrophysical and epidemiological data sets that the variances of the observations are accessible from an analytical treatment of the data collection process. Moreover, in a regression model, heteroscedastic measurement errors and equation errors are common situations when modelling such data. This article deals with the limiting distribution of the maximum-likelihood and method-of-moments estimators for the line parameters of the regression model. We use the delta method to achieve it, making it possible to build joint confidence regions and hypothesis testing. This technique produces closed expressions for the asymptotic covariance matrix of those estimators. In the moment approach we do not assign any distribution for the unobservable covariate while with the maximum-likelihood approach, we assume a normal distribution. We also conduct simulation studies of rejection rates for Wald-type statistics in order to verify the test size and power. Practical applications are reported for a data set produced by the Chandra observatory and also from the WHO MONICA Project on cardiovascular disease.  相似文献   
108.
Abstract

Statements made by children in a range of legal settings can irrevocably impact their family structure, relationships, and living environment. Because these statements can fundamentally alter children’s futures, efforts have been made to identify methods to enhance children’s reports by increasing comprehensiveness, completeness, and accuracy. Interviewer support has broadly been considered a method of interest, but variations in what constitutes “support” have highlighted the need for greater specificity in documenting how different facets of supportive behaviors relate to children’s reporting tendencies. In this review, we describe work focused on the effects of interviewer support, on children’s memory completeness and accuracy. We then describe to a subset of interviewer behaviors that encourage elaboration in dyadic interactions: back-channeling and vocatives. We present preliminary evidence suggesting that these utterances, referred to as implicit encouragement, can increase the amount of detail provided without compromising accuracy. Implications for custody evaluations are discussed.  相似文献   
109.
In this article, we propose a flexible cure rate model, which is an extension of Cancho et al. (2011 Cancho, V.G., Rodrigues, J., de Castro, M. (2011). A flexible model for survival data with a cure rate: A Bayesian approach. J. Appl. Stat. 38:5770.[Taylor &; Francis Online], [Web of Science ®] [Google Scholar]) model, by incorporating a power variance function (PVF) frailty term in latent risk. The model is more flexible in terms of dispersion and it also quantifies the unobservable heterogeneity. The parameter estimation is reached by maximum likelihood estimation procedure and Monte Carlo simulation studies are considered to evaluate the proposed model performance. The practical relevance of the model is illustrated in a real data set of preventing cancer recurrence.  相似文献   
110.
The authors examined the association between different meanings of cohabitation and fertility intentions. Using data from the Generations and Gender Surveys on 5,565 cohabiters from 9 European countries (Austria, Bulgaria, France, Germany, Hungary, Lithuania, Norway, Romania, and Russia), they proposed a cohabitation typology based on attitudes toward marriage, intentions to marry, and perceived economic deprivation. Despite substantial variation in the prevalence and types of cohabiting relationships across Europe, cohabitation has become a living arrangement within which childbearing intentions are commonly formed and at times carried out. The authors found that the meaning that cohabiters attached to their union influenced significantly their short‐term fertility intentions, net of other covariates. Cohabiters who viewed their unions as a prelude to marriage were the most likely to plan to have a child in the near future, both in Western and Eastern European societies. The association between fertility intentions and marriage intentions was particularly strong among cohabiters who do not as yet have children in common, but it was also present in a more muted form among cohabitating parents. The findings suggest that, although marriage and childbearing are becoming less closely linked life events, they are not disconnected decisions for a large majority of cohabiters across Europe.  相似文献   
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