In order to predict with 99% confidence the expected value of y for a given value of x in a simple linear regression , a random sample of ten observations is taken. Which of the following t-table values would be used?
A) 1.860
B) 2.306
C) 2.896
D) 3.355

Question

Quizplus · Accepted Answer

Since we are looking for a 99% confidence interval, we need to find the t-value that corresponds to a 0.005 (1-0.99/2) significance level and 9 degrees of freedom (n-2). Looking at the t-table, the closest value to 0.005 and 9 degrees of freedom is 3.355, which corresponds to Choice D. Therefore, we would use the t-value from Choice D to predict the expected value of y for a given value of x with 99% confidence.

In Order to Predict with 99% Confidence the Expected Value