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1. Explain how a survival curves is produced and what it means.
- graph showing the percentages of a newly
born population still alive as the age of members of the population increase
- shows death rates at different times of the life span
- suggests degree of mortality factors at different ages of the population
2. Describe changes in survival curves and intensity of mortality factors for U.S. populations during the twentieth century.
- dramatic decrease in childhood mortality
factors and childhood death rates early in the century
- gradual decline in mortality factors and death rates for elders in the later half of the century
3. Describe possible changes in survival curves and their effects on the total population if there are increases in mean longevity, in maximal longevity, or in both parameters.
- increase in ML -> shift in last part of curve
(survival of adult population) to the right; results in large increase
in number of elders, in percentage of elders, and in total population
- increase in XL -> shift only the tail of curve (survival of oldest elders) to the right; results in small increase in number of elders, percentage of elders, and in total population
- increase in ML and in XL -> very great shift in last part of curve (survival of adult population) to the right; results in very large increase in number of elders, in percentage of elders, and in total population
- increase in ML or in ML plus XL would lead to very rapid increase in population, and possibly overpopulation
4. Discuss implications from the current increases in elders and possible additional increases if ML or if ML plus XL increase.
- examples include all aspects of individual and societal conditions (e.g., housing, food, health care, need for gerontology education, employment opportunities, career opportunities, economic conditions, political conditions, lifestyles, ecological conditions, etc.)
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© Copyright 1999 - Augustine G. DiGiovanna - All rights reserved.
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