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201.
This paper examines the effects of introducing a variable dependency ratio in Dasgupta's (1969) model. We consider a case in which the probability of dying as well as the rate of participation in the labor force change with age. It is shown that the inclusion of those realistic demographic features slows down the optimal rate of population growth and increases the rate of consumption. In spite of the reduction in the rate of population growth, this rate can still be positive. The sensitivity of the solutions to changes in the demographic parameters of the model is examined.  相似文献   
202.
"This article reports findings that have emerged from an effort made at statistically measuring the effects of immigration on the earnings of U.S.-born youth. The presence of immigrants arriving before 1965 has a positive impact on youth earnings. Recently arrived immigrants impact negatively, however. These results are consistent with recent findings that the skill level of immigrants arriving within the last two decades is lower relative to that of immigrants arriving earlier. The results also show that the negative effects diminish as the youth ages, reflecting skill acquisition and job mobility of the young worker into jobs less vulnerable to competition from immigrant workers."  相似文献   
203.
The technique of participatory research in community development is based on the involvement of the beneficiaries of the research in the entire research process, including the formulation of the research design, the collection of data, interpretation of information collected, and the analysis of findings. Thus, research teams utilizing this approach are composed of villagers, farmers, unemployed people, local leaders, and educators. The research process thus offers an educational experience that helps to identify community needs and motivate community members to become committed to the solution of their own problems. Moreover, this approach challenges the prevalent notion that only professional researchers can generate knowledge for meaningful social reform. A participatory research technique, based on the concept of citizen enlightenment for community development, was adopted by the Department of Adult Education at the University of Ibadan in a study of rural poverty in Oyo State's Apasan villages. The research team, comprised of local leaders, peasant farmers, teachers, local students, and university students, identified the villages' isolation and food scarcity as major causes of poverty. 2 actions were taken in response to these findings: 1) the construction of a road linking the Apasan communities with the State capital, enabling villagers to travel to the town, sell their goods, and purchase needed items; and 2) formation of a primary cooperative society for multipurpose farming. These actions have solved the food problem, improved the villagers' earning capacity, and resulted in the return of numerous villagers who had migrated to towns to find wage employment. Because the villagers were directly involved in the study of their problems, they were able to become more aware of their social reality and make the changes needed to lift them out of poverty.  相似文献   
204.
This study proposes and demonstrates an analytic paradigm based upon a substantive categorization of a set of inmigration correlates. It exemplifies the notion of categorizing, analyzing according to the categorization, and subsequently discussing the phenomenon in more depth. The paradigm has 2 steps: 1) the variables are categorized according to the cells resulting from the intersection of a preferably small number of nominal dimensions and 2) the data are analyzed, directly anchored in the prior categorization. The data used is Israel's 1983 census macro-data gathered from the Central Bureau of Statistics for the Israeli towns with populations of at least 5000. The authors defined 6 variables as push variables and 4 as pull variables. Results of the regression employing push variables show that 4 variables accounting for 72% of inmigration were found to significantly predict inmigration: 1) unemployment, 2) percentage of Asians-Africans, 3) town size, and 4) religiosity. Within the pull classification, the regression analysis reveals that 2 of the 4 variables explain 31% of the inmigration variance: 1) educational level (26%) and 2) income (5%). The 1st regression analysis on the 2nd dimension shows that the percentage of Asian-African origin and town population size account for 32% of the immigration variance. In the 2nd regression analysis, unemployment explains 48% of the inmigration variance and educational level explains 8%. In the 3rd regression, only home crowding explains a significant amount of the immigration variance (19%). Results of a multiple regression analysis show that unemployment level, percentage of Asian-Africans, population size, and level of religiosity account for 72% of the inmigration variance. Thus, the characteristics of a town inmigrating (push variables) are demographic, economic, and social. However, the attractive features of a town are only economic. Among all economic factors, unemployment is primary. In addition, not only are both percentage of Asians-Africans and population size significantly deflective of inmigration, but each also plays a separate and independent role.  相似文献   
205.
This article discusses the role of migration in relieving population pressures, thus making continuing development possible, using small nations in the Caribbean and the South Pacific as examples. The Caribbean islands and many Pacific islands have used out-migration to ease population pressures in this century. Surplus labor has been emerging in various Caribbean nations, independent of the international marketing problems of plantation agriculture. Rural populations alienated from plantations have had to make do on questionable and/or remote land. Population surpluses appear to originate in rural areas, but little evidence exists to suggest that those surpluses are the basis for the emigration patterns of the Caribbean islands. Emigration does not solve population problems because when ambitious, skilled workers leave their country, their actions have little to do with the existence of domestic surplus labor and their leaving may do little to facilitate domestic labor absorption. Thus, if mini-states wish to sustain their hopes of economic expansion, they must find the means to employ their surplus labor. Since mainly skilled migrants leave, their going may actually slow development and retard opportunities for labor absorption. Population movements internal to the Caribbean region may further complicate surplus labor and/or population problems. If protective entry requirements impede normal inter-island relations, they may interfere with developmental processes. In general, migration is not a feasible strategy for population control for small island nations. While temporary migration has a more positive impact than other forms of migration, problems do exist. For example, temporary migration 1) can impose significant economic costs on the source-country, and 2) may result in the source country being unable to capitalize on its initial investment in training and education of temporary migrants. In conclusion, import substitution through cooperation between small island nations, production for export where feasible, and more attention to more sophisticated international service linkages hold a better prospect for material progress than relying on the export of surplus populations.  相似文献   
206.
A face-to-face survey conducted in 1984 with a sample of 1491residents of the Detroit metropolitan area (including an oversampleof older adults) and a reinterview of a random subset of theserespondents by telephone were used to compare the two modesof data collection across two age levels. Except for a tendencytoward a disproportionately large number of DK answers and adisproportionately large amount of interviewer assistance onthe telephone, respondents 60 years of age and older did notexhibit larger mode differences than did respondents under 60.For both age groups, response distributions were rather similar,suggesting little effect of mode. Likewise, response style differedlittle by mode, while a higher proportion of missing data (i.e.,"I don't know" answers) was given on the telephone. The responserate for the telephone reinterview was 90%, somewhat lower forolder than younger persons. The findings support the feasibilityof using the telephone for reinterviewing older adults.  相似文献   
207.
"Uncertainty in statistics and demographic projections for aging and other policy purposes comes from four sources: differences in definitions, sampling error, nonsampling error, and scientific uncertainty. Some of these uncertainties can be reduced by proper planning and coordination, but most often decisions have to be made in the face of some remaining uncertainty. Although decision makers have a tendency to ignore uncertainty, doing so does not lead to good policy-making. Techniques for estimating and reporting on uncertainty include sampling theory, assessment of experts' subjective distributions, sensitivity analysis, and multiple independent estimates." The primary geographical focus is on the United States.  相似文献   
208.
An attempt is made to develop a typology of the demographic transition based on the experience of 23 European countries. The typology is then used to examine the characteristics of the demographic transition in the socialist countries of Eastern Europe.  相似文献   
209.
Recent fertility trends in Poland are analyzed using data from a mail survey conducted in 1984. The demographic, social, and economic characteristics of women who gave birth in 1984, their husbands, and their parents are examined. The results show an increase in fertility in the early 1980s, particularly in urban areas.  相似文献   
210.
Bangladesh has a population of 115 million people, and the economic growth rate of 3.7% during the 1980s was undermined by rapid population growth. The annual population growth rate was 3% in the 1960s and early 1970s, 2.5% between 1981-91 decreasing to 2.3% in 1991. The average of number of children is 4.6/woman compared with 7 in the 1960s. Infant mortality dropped from 150/1000 births in 1976 to 118/1000 in 1991. Life expectancy rose from 47 to 54 years. The 1991 Contraceptive Prevalence Survey showed that 39.9% of married women under 50 use contraceptives in 1991 vs. 18.6% in 1981. The use of modern methods increased from 10.9% in 1981 to 31.2% in 1991, while traditional methods rose from 7.7% to 8.7%. Sterilization was most prevalent in 1981. 29,000 female family planning (FP) workers were aggressively engaged in dispensing FP services in 1990. The Social Marketing Company sells pills, condoms, and oral rehydration salts through 130,000 retail outlets. The 1989 Contraceptive Prevalence Survey showed that 40% of pill and condom users obtained them from this network, and 95.4% of women knew about 4 methods of contraception. In 1990 there were 120 private organizations providing contraceptive services. Some of the components of the government FP program include field worker distribution door-to-door of injectable contraceptives (50% injectable usage rate in the Matlab project); recordkeeping activities; a satellite clinic network with access to contraceptive services; and decentralization through the Upazila (subdistrict) approach. The logistics system of FP has improved the warehousing, transportation, and management information system. Foreign aid (mainly USAID) financing of contraceptives helped avert 14.4 million births between 1974-90. The increase of contraceptive prevalence to 50% by 1997 would avert another 21.9 million births during 1991-96 (replacement fertility requires 70% prevalence.  相似文献   
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