Identify each of the following statements as true or false and explain why:

A. A parameter is a population characteristic that is estimated by a coefficient derived from a sample of data.

B. A one-tail t test is used to indicate whether the independent variables as a group explain a significant share of demand variation.

C. Given values for independent variables, the estimated demand relation can be used to derive a predicted value for demand.

D. A two-tail t test is an appropriate means for testing direction (positive or negative) of the influences of independent variables.

E. The coefficient of determination shows the share of total variation in demand that cannot be explained by the regression model.