ABSTRACT

Observe that this is also equivalent to rejecting H0 whenever r 2=c, where the

constant c depends on the level of significance a of the test. Example 8.3.1. Consider the data given in Example 5.3.1. Let ?2 be the square of

the population multiple correlation coefficient between X6 and (X1,…, X5). The

square of the sample multiple correlation coefficient r2 based on 27 observations for each year’s data is given by

We wish to test the hypothesis at a=0.01 that the wheat yield is independent of the variables plant height at harvesting (X1), number of effective tillers (X2), length of ear (X3), number of fertile spikelets per 10 ears (X4), and number of grains per 10

ears (X5). We compare the value of (21/5)(r 2/(1-r2)) with a F5,21,0.01=9.53 for each

year’s data. Obviously for each year’s data (21/5)(r2/(1-r2))>9.53, which implies that the result is highly significant. Thus the wheat yield is highly dependent on (X1, …, X5).