
Chapter 14
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As discussed, the coef cient of determination leads to an important interpretation of the
regression model. In Example 14.1, r
2
is calculated as 0.9009. This indicates that 90.09% of the
variation in sales can be explained by the independent variable, that is, advertisement. This result
also explains that 9.91% of the variation in sales is explained by factors other than advertisement.
Figures 14.21, 14.22, and 14.23, are the partial regression outputs from MS Excel, Minitab,
and SPSS respectively, exhibiting coef cient of determination and other important results.
14.7.2 Standard Error of the Estimate
It has already been discussed ...