Question

STAT 464: INTRODUCTION TO BAYESIAN ANALYSIS

HOMEWORK

1. Legal cases of disputed paternity in many countries are resolved using blood tests. Laboratories make genetic determinations concerning the mother, child, and alleged father. You are on a jury considering a paternity suit. The mother has blood type O, and the alleged father has blood type AB. A blood test shows that the child has blood type B. What is the chance that the alleged father is in fact the real father, given that the child has blood type B? Here’s some information we need to solve the problem. According to genetics, there is a 50% chance that this child will have blood type B if this alleged father is the real father. Furthermore, based on incidence rates of B genes in the population, there is a 90% chance that this child would not have blood type B if this alleged father is not the real father. Based on other evidence (e.g. testimonials, physical evidence, records) presented before the DNA test, you believe there is a 75% chance that the alleged father is the real father.

Answer 1