(Problem 2: Minimum of Exponentials)
(Problem 2: Minimum of Exponentials)
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== Problem 2: Minimum of Exponentials ==
 
== Problem 2: Minimum of Exponentials ==
 
*(a)  <math>X_1</math> is an exponential random variable with parameter <math>\lambda_1</math>, and <math>X_2</math> with <math>\lambda_2</math>. Let <math>Y = \min(X_1,X_2)</math>. What is the PDF of <math>Y</math>? Is <math>Y</math> one of the common random variables?
 
*(a)  <math>X_1</math> is an exponential random variable with parameter <math>\lambda_1</math>, and <math>X_2</math> with <math>\lambda_2</math>. Let <math>Y = \min(X_1,X_2)</math>. What is the PDF of <math>Y</math>? Is <math>Y</math> one of the common random variables?
*(b)
+
*(b) Use induction to show that the minimum of <math>n</math> exponential random variables with parameter 1 is an exponential random variable with paramter <math>n</math>.
  
 
== Problem 3: Random Chord ==
 
== Problem 3: Random Chord ==
  
 
== Problem 4: Fire Station ==
 
== Problem 4: Fire Station ==

Revision as of 06:53, 30 September 2008

Instructions

Homework 5 can be downloaded here on the ECE 302 course website.

Problem 1: Coupon Collector

Each brand of candy bar has one coupon in it. There are $ n $ different coupons in total; getting at least one coupon of each type entitles you to a prize. Each candy bar you eat can have any one of the coupons in it, with all being equally likely. Let $ X $ be the (random) number of candy bars you eat before you have all coupons. What are the mean and variance of $ X $?

Problem 2: Minimum of Exponentials

  • (a) $ X_1 $ is an exponential random variable with parameter $ \lambda_1 $, and $ X_2 $ with $ \lambda_2 $. Let $ Y = \min(X_1,X_2) $. What is the PDF of $ Y $? Is $ Y $ one of the common random variables?
  • (b) Use induction to show that the minimum of $ n $ exponential random variables with parameter 1 is an exponential random variable with paramter $ n $.

Problem 3: Random Chord

Problem 4: Fire Station

Alumni Liaison

Ph.D. 2007, working on developing cool imaging technologies for digital cameras, camera phones, and video surveillance cameras.

Buyue Zhang