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41.
We summarize and comment on the policy sections of the articles in this issue concerned with the health effects of residential environments. We review the implications in the context of public policies implemented over at least the last century to improve the least, as well as most, expensive housing. We make the argument that public policy can reduce but not eliminate the contribution of housing to the differences in health between the wealthy and poor. We conclude that the applied value of work such as that presented in this issue arises from its contribution to sustaining the improvements in health enjoyed over the last century, not from whether it helps eliminate the gap in health between the poor and wealthy .  相似文献   
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The ongoing debate over the flaws in the nation's welfare system centers primarily on two highly charged social ills: teen-age pregnancy and long-term dependence on public assistance. For the poorest and fastest growing segment of the welfare population—homeless mothers—these problems are both severe and inextricably linked. At an alarmingly young age, these women are becoming trapped in a chaotic cycle that offers little structure and few alternatives.  相似文献   
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In any analysis of a decision problem involving public risks, ethical implications are introduced. In some cases, these ethical implications may be introduced simply because an analysis is being done. Additional ethical implications may be inherently part of the methodology being utilized or introduced into the specific analysis of the decision problem. In this paper, we investigate where and how ethical implications enter when using the methodology of decision analysis to examine problems involving public risks. We conclude that the methodology of decision analysis is sufficiently robust to allow for numerous different ethical viewpoints to be accounted for in any specific analysis. Stated alternatively, decision analyses of public risks can be conducted in a manner consistent with utilitarianism, deontological theories, libertarianism, egalitarianism, and so forth. However, any specific analysis has embedded within it numerous ethical implications. This suggests that the careful ethical scrutiny of analyses involving the methodology of decision analysis should be placed on the specific application and not on the methodology per se or on the fact that an analysis is undertaken.  相似文献   
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Abstract Previous models of community satisfaction and attachment have not included personal economic attitudes and behaviors as independent variables. Their inclusion is theoretically justified when residents of communities are viewed as consumers in a larger social/economic context first and residents of a particular community second. As locally-oriented economic processes—once part of the community experience—were removed to nonlocal markets, local economic and demographic attributes became less important to rural residents' experience of community. In two rural communities with extreme scores on a service center viability index, satisfaction with employment and location of employment are important predictors.  相似文献   
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Two assumptions used in risk assessment are investigated: (1) the assumption of fraction of lifetime dose rate assumes that the risk from a fractional lifetime exposure at a given dose rate is equal to the risk from full lifetime exposure at that same fraction of the given dose rate; (2) the assumption of fraction of lifetime risk assumes that the risk from a fractional lifetime exposure at a given dose rate is equal to that same fraction of the risk from full lifetime exposure at the same dose rate. These two assumptions are equivalent when risk is a linear function of dose. Thus both can be thought of as generalizations of the assumption that cancer risk is proportional to the total accumulated lifetime dose (or average daily dose), which is often made to assess the risk from short-term exposures. In this paper, the age-specific cumulative hazard functions are derived using the two-stage model developed by Moolgavkar, Venzon, and Knudson for situations when the exposure occurs during a single period or a single instant. The two assumptions described above are examined for three types of carcinogens, initiator, completer, and promoter, in the context of the model. For initiator and completer, these two assumptions are equivalent in the low-dose region; for a promoter, using the fraction of lifetime risk assumption is generally more conservative than that of the fraction of lifetime dose rate assumption. Tables are constructed to show that the use of either the fraction of lifetime dose rate assumption or the fraction lifetime risk assumption can both underestimate and overestimate the true risk for the three types of carcinogens.  相似文献   
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A nonparametric estimator of the probability distribution of time-to-tumor is incorporated into an algorithm for calculating linearly extrapolated dosage limits from an animal carcino-genesis bioassay. The procedure is illustrated with tumor data from a mouse bioassay with 2-acetylaminofluorene. Extrapolated dosage limits for an excess risk of 10-6 differ by only a factor of 2 across the six replicates of the experiment.  相似文献   
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