# Question

The figure at the top of the page is based on data from the article “Root and Shoot Competition Intensity Along a Soil Depth Gradient” (Ecology [1995]: 673– 682). It shows the relationship between aboveground biomass and soil depth within the experimental plots. The relationship is described by the estimated regression equation: biomass = 29.85 1 25.29(soil depth) and r2 = .65; P < 0.001; n = 55. Do you think the simple linear regression model is appropriate here? Explain. What would you expect to see in a plot of the standardized residuals versus x?

## Answer to relevant Questions

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