p = fraction supporting McCain

To find p, ask 1000 people who they support.

declare answer = # supp Mc / 1000 = X / 1000

X = # supp Mc in poll

X is binomal(1000,p)

E[X] = 1000*p

Var(X) = 1000*p*(1-p)

Pr[ |(X/1000) - p | >= 0.1 ]

= Pr[ | X - 1000*p | >= 1000 ]

<= Var(X)/100^2

= 1000*p*(1-p)/100^2

= p*(1-p)/10

Pr[ | (X/1000) - p | >= 0.1 ] <= (1/4)/10 = 1/40


Back to ECE302 Fall 2008 Prof. Sanghavi

Alumni Liaison

BSEE 2004, current Ph.D. student researching signal and image processing.

Landis Huffman