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An alternative purging method: controlling the composition-dependent interaction in an analysis of rates
1Population Studies Center, University of Michigan, Ann Arbor 48104.
Demography
|November 1, 1989
Summary
This study introduces partial CD purging, a new demographic research method. It offers rates invariant to composition changes, unlike prior techniques.
Area of Science:
- Demographic research
- Statistical methodology
Background:
- Clogg's purging method is widely used in demography for controlling composition-group interactions.
- Existing methods may be sensitive to changes in the marginal distribution of composition.
Purpose of the Study:
- To propose an alternative method, partial CD purging.
- To develop a technique invariant to changes in the marginal distribution of composition.
Main Methods:
- Introduction of the partial CD purging method.
- Mathematical exploration of relationships with other statistical techniques.
Main Results:
- Partial CD purging controls for the interaction between composition and the dependent variable.
- Purged rates from the new method are invariant to marginal distribution shifts.
Conclusions:
- Partial CD purging offers an improvement over existing methods by providing invariant rates.
- The new method enhances the robustness of demographic analyses.
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