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891.
892.
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   
893.
"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   
894.
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   
895.
This paper extends the author's recent work on dynamically consistent consequentialist social norms for an unrestricted domain of decision trees with risk to trees in which the population is a variable consequence — i.e., endogenous. Given a form of ethical liberalism and ethical irrelevance of distant ancestors, classical utilitarianism is implied (provided also that a weak continuity condition is met). The repugnant conclusion that having many poor people may be desirable can be avoided by denying that individuals' interests extend to the circumstances of their birth. But it is better avoided by recognizing that potential parents have legitimate interests concerning the sizes of their families.That action is best, which procures the greatest happiness for the greatest numbers. Francis Hutchison (1725).An abiding interest in concepts of optimality for the choice of population has been stimulated by frequent discussions with Partha Dasgupta. This paper was presented at the seminar on Distributive Justice and Inequality at the Wissenschaftskolleg zu Berlin, May 1986. I am grateful to the audience for their helpful comments, especially Maurice Salles and Patrick Suppes, and especially to John Weymark for carefully reading and suggesting distinct improvements to the earlier version.  相似文献   
896.
Excuse-making is defined, and the issues of deception and verbal/nonverbal presentations are discussed in regard to the excuse process. Subsequently, the deception and verbal/nonverbal issues are described in greater detail in the context of whether the excuse occurs temporally after a negative outcome (retrospective), before a negative outcome (anticipatory), or as part of the characterological makeup of the person (incorporated). Going from retrospective to anticipatory to incorporated excuses, it is concluded that the role of nonverbal factors increases. Likewise, in the progression from making to being the excuse, it is argued that self- and other-deception also become more pervasive.  相似文献   
897.
It was tested whether professional actors would be able to communicate emotional meaning via facial expression when this is presented to judges without context information. Forty takes were selected from movies, depicting a female or a male actor in close-up showing facial expression. These close-ups were selected by two expert judges, who knew the complete movie and had to agree on the emotion expressed or expected to be expressed by the female or male actor in the respective take. Five takes each were selected to represent the basic emotions of joy, sadness, fear, and anger. Twenty takes each were selected showing female and male actors. These 40 takes (edited in random order onto video tape) were presented to 90 judges (about half female and half male; about half younger pupils and about half older ones), whose task it was to judge the emotion(s) expressed on nine 5-point-emotion scales. Results indicated that female actors are somewhat better (though not statistically significant) in communicating emotion via facial expression without context than male actors are. Furthermore, significant interactions between portrayed emotion and gender of actors were found: While recognition rate for joy is very high and identical for both genders, female actors seem to be superior in communicating fear and sadness via facial expression, while male actors are more successful in communicating anger. A display rule approach seems to be appropriate for the interpretation of these results, indicating that gender-specific attempts to control/inhibit certain emotions do not only exist in real life, but also in movies.The research reported here was supported by a grant of the Deutsche Forschungsgemeinschaft (WA 519/2-2). I thank Uwe Balser and Tina Mertesacker for their help in selecting the stimuli, preparing the judgment tapes, recruiting subjects and conducting the study.  相似文献   
898.
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   
899.
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   
900.
In a six-year study on a locked psychiatric hospital unit for adolescents, first patients and then their families became integrated into the interdisciplinary treatment team. The results were universally beneficial. After initial resistance and some fine tuning of their skills, the staff became strong supporters of the program. Parents, no longer one down, developed a close working relationship with the therapists and milieu staff. Treatment planning and implementation was enriched by the interaction and dissension was minimized. Most important of all, the adolescents improved more rapidly and hospital stays were significantly shortened.  相似文献   
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