Part 1 ; Identify a group of points that represent a subgroup of menu items
(for example the salads, or dessets, etc.) from your original data, and separate them as a
distinct smaller data set. Then create new scatterplots with regression equation, r, and R2,for both the new group and the remaining group of data. Compare those two models to
each other and to the original full data set model, explaining how they are different,
interpreting the new equations, and explaining why they would be different. Finally, decide
which model is the better predicter if they are appreciably different. Expected length: 1-2
pages of writing; in other words, there should also be scatterplots that don’t count in the
length.
Part 2 ; Identify an outlier or high leverage point (or two or three) and
eliminate it from your data set. Then create a new scatterplot, and recalculate your
regression equation, r, and R2
, using the remaining data points. Compare the new results to
your original results. Explain how they are different, interpret the new equation, and
explain why they would be different. Finally, decide which model is the better predicter if
they are appreciably different. Expected length: 1-2 pages of writing; in other words, there
should also be scatterplots that don’t count in the length.