SOA Exam P Sample Question 82

Study guide: Exam P-1

A diagnostic test for the presence of a disease has two possible outcomes: 1 for disease present and 0 for disease not present. Let X denote the disease state (0 or 1) of a patient, and let Y denote the outcome of the diagnostic test.

The joint probability function of X and Y is given by:

• P[X=0, Y=0] = 0.800
• P[X=1, Y=0] = 0.050
• P[X=0, Y=1] = 0.025
• P[X=1, Y=1] = 0.125

Calculate Var(Y \mid X=1).

• A) 0.13
• B) 0.15
• C) 0.20
• D) 0.51
• E) 0.71

Answer this question and see the worked solution

Concepts tested

• Conditional Probability Function
• Variance for Conditional and Marginal Distributions
• Discrete Univariate Distributions

More questions from this set

• SOA Exam P Sample Question 81
• SOA Exam P Sample Question 83