Answer the following questions based on Section 4.1.5: Transformations for the response and predictors.

Consider the following data:

X 2.3 1.8 2.2 1.2 1.6 2.6 1.4 1.1 1.2 1.6
Y 1.7 1.6 2.6 0.9 1.8 3.1 1.4 1.0 1.1 1.4
Use statistical software to fit a simple linear regression model with response variable, Y, and predictor variable, X (call this model 1). Then fit another simple linear regression model with response variable, loge(Y), and predictor variable, loge(X) (call this model 2). Use the fitted models to answer the following questions.

1. 

Model 2 with response variable, loge(Y), and predictor variable, loge(X), provides a more useful description of the association between Y and X than that of model 1 with response variable, Y, and predictor variable, X, because:

2. 

True or False? Comparing the magnitude of the regression standard error, s, in model 2 (0.1687) with that in model 1 (0.3292) tells us nothing about which model provides a more useful description of the association between Y and X.

3. 

True or False? The fact that for model 2 the variation of the residuals remains constant as X increases, whereas for model 1 the variation of the residuals tends to increase as X increases, indicates that model 1 provides a more useful description of the association between Y and X than that of model 2.

4. 

True or false? The reason that model 2 is a linear regression model is because the logarithmic transformations to Y and X “cancel out.”

5. 

True or false? The natural logarithm transformation tends to "spread out" lower values and "pull in" higher values.

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