2 quick questions - please answer in one paragraph or less/ea - no plagiarism

1. Define regression line. What does the regression emphasized in the textbook minimize? Is this the only regression line that it is might be desirable to construct? What other one might be desirable? Suggest some situations that might be appropriate for each and discuss.

2. If there is no relationship between the X and Y variables and we desire to predict Y given X using a least-squares criterion, it is best to predict for every Y score. Is this correct? If so, explain why. (Hint: one of the properties of the mean might be helpful here)