A researcher is trying to decide whether or not to add another variable to his model. He has estimated the following model from a sample of 28 observations.

Y = 23.62 + 18.86 X1 + 24.72 X2

SSR = 1,326

He has also estimated the model with an additional variable X3. The results are

Y = 25.32 + 15.29X1 + 7.63X2+ 12.73 X3

SST = 2751 SSR = 1,451

a. Select the test statistic and calculate its value

b. Identify critical value(s) for the test statistics.

c. Using P-Value approach make a conclusion to take a business decision.