This preview shows pages 1–2. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: Statistics 5101, Fall 2010: Homework Assignment 7 Solve each problem. Explain your reasoning. No credit for answers with no explanation. If the problem is a proof, then you need words as well as formulas. Explain why your formulas follow one from another. 71. If X has the Gam( , ) distribution, we calculated in class that E ( X ) = ( + ) ( ) . (a) Find E ( X 2 ) (b) Find var( X ). None of your answers should contain gamma functions (use the gamma function recursion formula to simplify). 72. If X has the Beta( 1 , 2 ) distribution, show that E { X 1 (1 X ) 2 } = ( 1 + 2 )( 1 + 1 )( 2 + 2 ) ( 1 )( 2 )( 1 + 2 + 1 + 2 ) Hint: use the fact that the PDF of the beta distribution integrates to one, just like we did for the gamma distribution. You may ignore the issue of when the integral exists (it exists when 1 &gt; 1 and 2 &gt; 2 , but we dont know how to prove that yet)....
View
Full
Document
This note was uploaded on 12/01/2010 for the course STAT 5101 taught by Professor Staff during the Fall '02 term at Minnesota.
 Fall '02
 Staff
 Statistics

Click to edit the document details