In: Statistics and Probability
Consider the data.
xi |
3 | 12 | 6 | 20 | 14 |
---|---|---|---|---|---|
yi |
65 | 40 | 60 | 15 | 20 |
The estimated regression equation for these data is
ŷ = 75.75 − 3.25x.
(a)
Compute SSE, SST, and SSR using equations
SSE = Σ(yi − ŷi)2,
SST = Σ(yi − y)2,
and
SSR = Σ(ŷi − y)2.
SSE = SST = SSR =
(b)
Compute the coefficient of determination
r2.
(Round your answer to three decimal places.)
r2
=
Comment on the goodness of fit. (For purposes of this exercise, consider a proportion large if it is at least 0.55.)
The least squares line did not provide a good fit as a large proportion of the variability in y has been explained by the least squares line.The least squares line provided a good fit as a large proportion of the variability in y has been explained by the least squares line. The least squares line did not provide a good fit as a small proportion of the variability in y has been explained by the least squares line.The least squares line provided a good fit as a small proportion of the variability in y has been explained by the least squares line.
(c)
Compute the sample correlation coefficient. (Round your answer to three decimal places.)