Concept explainers
Critical Thinking: Interpreting Computer Printouts We use the form
A Minitab printout provides
Predictor | Coef | SE Coef | T | P |
Constant | 318.16 | 28.31 | 11.24 | 0.002 |
Elevation | -30.878 | 3.511 | -8.79 | 0.003 |
s = 11.8603 R-Sq = 96.3%
Notice that “Elevation” is listed under “Predictor.” This means that elevation is the explanatory variable x. Its coefficient is the slope b. “Constant” refers to a in the equation
(a) Use the printout to write the least-squares equation.
(b) For each 1000-foot increase in elevation, how many fewer frost-free days are predicted?
(c) The printout gives the value of the coefficient of determination
(d) Interpretation What percentage of the variation in y can he explained by the corresponding variation in x and the least-squares line? What percentage is unexplained?
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Understanding Basic Statistics
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