In exercise 12, the following data on x = average daily hotel room rate and y = amount spent on entertainment (The Wall Street Journal, August 18, 2011) lead to the estimated regression equation ŷ = 17.49 + 1.0334x. For these data SSE = 1541.4.
City: Boston Denver Nashville New Orleans Phoenix San Diego San Francisco San Jose Tamp
Room Rate ($) 148 96 91 110 90 102 136 90 82
Entertainment: 161 105 101 142 100 120 167 140 98
a. Predict the amount spent on entertainment for a particular city that has a daily room rate of $89 (to 2 decimals).
Answer: 109.46
b. Develop a 95% confidence interval for the mean amount spent on entertainment for all cities that have a daily room rate of $89 (to 2 decimals
$____ to $_____.
c. The average room rate in Chicago is $128. Develop a 95% prediction interval for the amount spent on entertainment in Chicago (to 2 decimals).
$___ to $____.
I already solved part A. I just need help with B and C.
For part B I believe the equation to use is t alpha/2(n-2)*s SQRT (1/n + (x - xbar)^2 / SSxx).
For part C I think the equation is t alpha/2(n-2)*s SQRT (1 + 1/n + (x - xbar)^2 / SSxx).
The issue I am having is I don't know how what to plug into each of these equations. I feel like I am missing some information. Please help, thank you.
1 answer