Let X1, X2, . . . , Xn be random variables denoting
80.   Let X1, X2, . . . , Xn be random variables denoting n independent bids for an item that is for sale. Suppose each Xi is uniformly distributed on the interval [100, 200]. If the seller sells to the highest bidder, how much can he expect to earn on the sale? [Hint: Let Y = max(X1, X2, . . . , Xn). Find FY(y) by using the results of Section 5.5 or else by noting that Y y iff each Xi is y. Then obtain the pdf and E(Y).]
81.   Suppose a randomly chosen individual s verbal score X and quantitative score Y on a nationally ad- ministered aptitude examination have joint pdf
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2
f 1x, y 2 = • 512x + 3y 2   0 x 1, 0 y 1
0Â Â Â Â Â Â Â Â Â Â Â Â otherwise
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You are asked to provide a prediction t of the indi- vidual s total score X + Y. The error of prediction is the mean squared error E[(X + Y - t)2]. What value of t minimizes the error of prediction?
Answers
Status NEW
Posted 02 May 2017 12:05 PM
My Price 5.00
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file 1493727791-answer1.docx preview (164 words )
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