The ability of ecologists to identify regions of greatest species richness
could have an impact on the preservation of genetic diversity, a major
objective of the World Conservation Strategy. The article "Prediction of
Rarities from Habitat Variables: Coastal Plain Plants on Nova Scotian
Lakeshores" (Ecology [1992]: 1852 - 1859) used a sample of \(n=37\) lakes to
obtain the estimated regression equation \(\begin{aligned} \hat{y}=& 3.89+.033
x_{1}+.024 x_{2}+.023 x_{3} \\ &+.008 x_{4}-.13 x_{5}-.72 x_{6}
\end{aligned}\) where \(y=\) species richness, \(x_{1}=\) watershed area, \(x_{2}=\)
shore width, \(x_{3}=\) drainage \((\%), x_{i}=\) water color (total color units),
\(x_{5}=\) sand \((\%)\), and \(x_{6}=\) alkalinity. The coefficient of multiple
determination was reported as \(R^{2}=.83 .\) Use a test with significance level
\(.01\) to decide whether the chosen model is useful.