=+11. In the same way that bysb is the t-ratio for testing H0:  5 0, the t-ratio aysa is appropriate for testing H0:  5 0, where sa is the estimated standard deviation of the statistic a and the test is again based on n 2 2 df. The null hypothesis says that the vertical intercept of the population line is zero, so that the line passes through the origin (0, 0). Carry out this test using the information given in Exercise 10.

Section 11.2 Exercises