4.3. Referring to the previous problem, again suppose that auniform prior is placed on the proportion ?, and that from a randomsample of 327 voters, 131 support the sales tax. Also suppose thatthe newspaper plans on taking a new survey of 20 voters. Let y?denote the number in this new sample who support the sales tax.
Find the posterior predictive probability that y? = 8.
Find the95% posterior predictive interval for y?.Do this byfinding the predictive probabilities for each of the possiblevalues of y? and ordering them from largest probability tosmallest. Then add the most probable values of y? into yourprobability set one at a time until the total probability exceeds0.95 for the first time.
