Question: =+2.30. Let X1; X2; ... ; Xn be a random sample from the exponential distribution fX x2y 1 ex=2y; x50; y > 0, and let
=+2.30. Let X1; X2; ... ; Xn be a random sample from the exponential distribution fX ðxÞ¼ð2yÞ
1 ex=2y; x50; y > 0, and let the ordered X ’s be denoted by Y1 4Y2 4 4Yn. Assume that the underlying experiment is such that Y1 becomes available first, then Y2, and so on (for example, in a life-testing study) and that the experiment is terminated as soon as Y is observed for some specified r.
ðaÞ Show that the joint probability density function of Y1;Y2; ... ;Yr is
ð2yÞ
r n!
ðn rÞ!
exp
Pr i¼1 yi þ ðn rÞyr 2y
04y1 4 4yr < 1
ðbÞ Show that y1½
Pr i¼1 Yi þ ðn rÞYr has a chi-square distribution with 2r degrees of freedom.
Step by Step Solution
There are 3 Steps involved in it
Get step-by-step solutions from verified subject matter experts
