In Exercise 12.21 it would not have made much of a difference whether we combined the data across the three intervals or not. Under what conditions would you expect that it would make a big...

In Exercise 12.21 it would not have made much of a difference whether we combined the data across the three intervals or not. Under what conditions would you expect that it would make a big difference?

 Using the data in Epineq.dat, compute both the linear and quadratic trend tests on the three drug dosages. Do this separately for each of the three intervals. (Hint: The linear coefficients are [20.597110, 20.183726, 0.780836], and the quadratic coefficients are [0.556890, 20.795557, 0.238667].)