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101.
Sources of drug information among adolescent students 总被引:1,自引:0,他引:1
E Mirzaee P M Kingery B E Pruitt G Heuberger R S Hurley 《Journal of drug education》1991,21(2):95-106
A sample of 1023 eighth and tenth grade students in small to medium-sized central Texas school districts was assessed to determine the amount of information they receive from ten sources about six categories of drugs. The amount of information males reported receiving about each drug category was significantly greater than what females reported, and the amount of information that eighth graders reported receiving about each drug category was significantly greater than what tenth graders reported. Television was the primary source of drug information for all categories of drugs except inhalants, for which friends and television were equally important sources. Parents and printed media (magazines or newspapers) were of secondary importance, followed by friends and teachers. Adolescents were less likely to receive drug-related information from experience, siblings, church, doctors, and police. The reliance on the mass media for drug information in smaller school districts is a pattern which has been previously observed in larger urban districts. This consistency suggests that mass media approaches to drug education are likely to be as effective in rural areas and smaller towns as they are among urban adolescents. Implications for television programming are discussed. 相似文献
102.
103.
The latest advances in artificial intelligence software (neural networking) have finally made it possible for qualitative researchers to apply the grounded theory method to the study of complex quantitative databases in a manner consistent with the postpositivistic, neopragmatic assumptions of most symbolic interactionists. The strength of neural networking for the study of quantitative data is twofold: it blurs the boundaries between qualitative and quantitative analysis, and it allows grounded theorists to embrace the complexity of quantitative data. The specific technique most useful to grounded theory is the Self‐Organizing Map (SOM). To demonstrate the utility of the SOM we (1) provide a brief review of grounded theory, focusing on how it was originally intended as a comparative method applicable to both quantitative and qualitative data; (2) examine how the SOM is compatible with the traditional techniques of grounded theory; and (3) demonstrate how the SOM assists grounded theory by applying it to an example based on our research. 相似文献
104.
This paper presents results of a validation survey of abortion conducted in Tallinn, Estonia in April and May 1992. The sample was drawn from patient records in a maternity hospital. Women who had an abortion in that hospital in 1991 were asked about recent abortions as part of a survey about women’s health. More than 80% of the respondents reported having a recent abortion. Some respondents misreported their abortion as a miscarriage. Moreover, some variation in reporting was associated with respondents’ characteristics. Ethnic Estonians were less likely to report their abortion than were Russians, women over age 40 were less likely to report the abortion than younger women, and women who had the abortion late in the first trimester were less likely to report that abortion. There was some evidence that unmarried women were less likely than married women to report their abortion, and that women who had borne three or more children were less likely to report their abortion than women who had borne fewer children. These differences probably stem from the extent to which pregnancy or abortion is considered stigmatizing for women in different situations. 相似文献
105.
106.
盆景艺术风格是盆景艺术家的创作个性在作品中的外在表现 ,它对盆景艺术的发展起着很重要的作用 ,人们对盆景的感性认识直接来源于盆景的风格。大部分盆景方面的书和文章都会涉及到盆景艺术风格的问题 ,但是 ,迄今为止对盆景艺术风格的形成和发展进行过系统研究的人还不是很多。基于对艺术发展规律和中国各种艺术风格盆景发展历史的研究 ,该文详细论述了影响盆景艺术风格形成和发展的内在、外在因素及它们之间的关系 ,并对怎样给我国盆景艺术注入新的活力提出了一些建议 ,对我国盆景艺术的发展和创新起到一定的指导作用 相似文献
107.
Russia’s role in ‘animation’ of the Kyoto Protocol was crucial. Its initial vacillation on ratification was predominantly
due to political bargaining with the EU. Domestic economic rationales [i.e. impacts of emission trading and Joint Implementation
(JI) projects] were important to a much lesser extent and environmental motives did not seem to play any role in the decision.
Since the Protocol entered into force, there have been significant delays in complete establishment of policy implementation
frameworks, which are necessary for Russia to start benefiting from JI and emission trading. Only recently, in 2007, have
GHG inventories and a national registry been established and the responsibilities for implementation of the Protocol and JI
among the government departments have been distributed only to a certain extent. Some constraints hindering JI projects, such
as vague legislation, an unfavourable economic climate, lack of commitment to JI projects, corruption, xenophobia, state and
agency ‘capture’ still remain.
相似文献
108.
Laura Bernardi Andreas Klärner Holger von der Lippe 《Revue europeenne de demographie》2008,24(3):287-313
This article contributes to the ongoing debate on the economic determinants of fertility behavior by addressing the role of
job insecurity in couples’ intentions concerning parenthood and its timing. It starts from the hypothesis that cultural values
moderate individuals’ reactions to job insecurity and the way it is related to family formation. With a systematic thematic
content analysis of a set of semi-structured interviews with childless men and women around the age of 30 in eastern and western
Germany, we are able to show that there are substantial differences in the consequences of job insecurity on intentions to
have a first child. In western Germany, a relatively secure job career is expected to precede family formation, and this sequence
of transitions is rather rigid, whereas in eastern Germany job security and family formation are thought of and practiced
as parallel investments. We suggest that the lack of convergence in family formation patterns between eastern and western
Germany after the unification of the country in 1990 is partially related to different attitudes toward job insecurity in
the two contexts. 相似文献
109.
110.
Michael Kohler 《AStA Advances in Statistical Analysis》2008,92(2):153-178
American options in discrete time can be priced by solving optimal stopping problems. This can be done by computing so-called
continuation values, which we represent as regression functions defined recursively by using the continuation values of the
next time step. We use Monte Carlo to generate data, and then we apply smoothing spline regression estimates to estimate the
continuation values from these data. All parameters of the estimate are chosen data dependent. We present results concerning
consistency and the estimates’ rate of convergence. 相似文献