Hi, In Chapter 11, section 2.4, the "mean response" and the "individual response" are described. I don't really get what this means, particularly the mean response*. In the practice questions at the end of the chapter, 11.5 (iv) asks for the mean finals paper score for an individual entrance score of 53. In 11.7 (ii) we are asked for the estimate of the average score for class X5 containing 15 students. What is the difference conceptually? How can an individual exam entrant have a "mean score"? Thanks, Eleanor *Pun only partially intended.
Probably a bit late for an answer now - but it's talking about the predicted value. The mean predicted value is on the regression line (a confidence interval for the predicted values is around this line). The individual predicted value is for an actual individual data point that is not necessarily on the regression line (a confidence interval for the predicted value is about this point). If you recall the individual points are an error term away from the line.