From a beginners point of view Jeff can become too involved and go over peoples heads too easily. I make many mistakes and am very open to admit them all. I'd no idea about the difference being shown regarding the 'r' and R^2, I'd not recognised it, taking the computer program as being correct just not understanding why it did not show a minus 1.
No I have not carried out any detailed studies of 'r' and R^2, that is not part of the written material in the book, in fact R^2 is not mentioned in the book at all, . and I didn't even pick up on that point between the book and the computer, I just asked why the computer did not show -1.
Post 15 explained all the understanding required in plain text. Sometimes there is a lot to be said for KISS when dealing with learners. Remember Basics, basics and more basics. I'm no experienced expert by any stretch of the imagination.
