1.Suppose that for a given data set, s2x=440,s2y=820,r=0.35,n=7
Then the regression standard error is:
2.Suppose that a regression yields the following sum of squares: Σ(yi-y¯)2=200, Σ(yi-yˆi)2=90, Σ(yˆi-y¯)2=110
Then the percentage of the variation in y that is explained by the variation in x is: