Question

Problem 2: 10 points Suppose that X is a random variable with the probability mass function, 10-k), n (n -1) for k=1, 2, ,n, where n 22. 1. Derive the expected value of X. 2. Determine the variance of X. 3. Derive the second moment of X.

0 0
Add a comment Improve this question Transcribed image text
Answer #1

Here , the probability mass function of X is given,

one needs to understand the basic definition of expectation of X .

I have provided some important formulas needed for this question.

丁mportant formula to remember K 디 2. 6 second moment of X E (x2x is a γand om variable with probability mass fmcion Devive Expectrtd value ofX ie Eox By definahon 2. に! fakinq Constant termsoside the SummaHon -2 nin-) K=1 am 2. n-i3(n-1) 30n -) 2 3(n-1 a1- b2- (a+b)(a-b) 3 in-) 3 21 Determine vanence of X· N(x) Vanene 1S 9Ver) by 2 , 2 (n-k) n(n-) ー.. substituting expression takiny constant termjs outside the Summation n(n-)2. 4 2 nin-) n (n+ 3 (n-1) 2(n-) expanding using Formula ca+ b)a+ b2 2 (6 6 (n-) 6 E (X2): n(n+i) ωhich is nothing but second moment 0t X This answers part3. as Second momen+ ot XO W 3 Cn+1)2 6x9 5 4 Factorizinj the teyms v(x) = (n+9(n-2)3 Derive the second moment ot X This has been derived in pavt 2 6

Add a comment
Know the answer?
Add Answer to:
Problem 2: 10 points Suppose that X is a random variable with the probability mass function,...
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for? Ask your own homework help question. Our experts will answer your question WITHIN MINUTES for Free.
Similar Homework Help Questions
ADVERTISEMENT
Free Homework Help App
Download From Google Play
Scan Your Homework
to Get Instant Free Answers
Need Online Homework Help?
Ask a Question
Get Answers For Free
Most questions answered within 3 hours.
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT