Bayes Theorem

# 1 is not dd then ii1 must be dd refer back to

This preview shows pages 2–3. Sign up to view the full content.

If II.1 is not Dd, then II.1 must be dd (refer back to pedigree if confused, II.1 can only be Dd or dd; so if not Dd, then II.1 must be dd). Plug in all the values into the equation: P(A|B) = (P(B|A)P(A)) / ((P(B|A)P(A) + P(B|nA)P(nA)) = ((1/2) 3 (1/2)) / ((1/2) 3 (1/2) + (1) 3 (1/2)) = (1/16) / ((1/16) + (1/2)) = 1/9 Thus the overall probability that II.1 is Dd is 1/9. 3. Genetic Counseling Method The genetic counseling students here at UM have a really cool and systematic way of dealing with Bayes’ Theorem. They utilize the following chart: Probability Event A Event B Prior a b Condition c d Joint ac bd Posterior ac/(ac+bd) bd/(ac+bd) We need to define what Events A and B are. Let A = II.1 is Dd, and B = II.1 is dd. Event B is basically Event “ not A” (nA). Before we fill in the chart, we need to know what Prior probability and Condition probability are. The rest of the chart is straightforward. Prior probability = the “original” probability that II.1 is either Dd or dd (depending on which event you’re looking at).

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Condition probability = the additional condition that modifies the prior probability. In this problem, the condition is having 3 children who’re all dd.
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern