In regression modeling, for t tests about regression parameters, df n number of parameters in equation for the mean a Explain why df n 2 for the model y x b Chapter 8 discussed how to estimate a single mean Treating this as the parameter in a simpler regression model, y , with a single parameter, e...

a df n the number of parameters for the ...

In regression modeling, for t tests about regression parameters, df = n - number of parameters in

Question:

In regression modeling, for t tests about regression parameters, df = n - number of parameters in equation for the mean.
a. Explain why df = n - 2 for the model μy = α + βx.
b. Chapter 8 discussed how to estimate a single mean μ. Treating this as the parameter in a simpler regression model, μy = μ, with a single parameter, explain why df = n - 1 for inference about a single mean.