Equations to Describe Population Based Parametric Mixtures of Logistic Regressions




Joint density of birth weight and occurrence of death for the 2-subpopulation case
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Birth-weight density:
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img is the mixing proportion
img is the Gaussian density with mean img and variance img truncated at 0.

Probability of death conditioned on birth:
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An infant of birth weight x in the ith sub-population has probability of dying given in quadratic logistic form:
img
img is the probability that this child is from sub-population 1 given it has birth weight x.
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