A research project was conducted to study the relationships among intelligence, aphasia, and apraxia.

The subjects were patients with focal left hemisphere damage. Scores on the following variables were obtained through the application of standard tests.

Y ¼ intelligence X1 ¼ ideomotor apraxia X2 ¼ constructive apraxia X3 ¼ lesion volume pixels ð Þ

X4 ¼ severity of aphasia The results are shown in the following table. Find the multiple correlation coefficient and test for significance. Let a ¼ :05 and find the p value.

Subject Y X1 X2 X3 X4 1 66 7.6 7.4 2296.87 2 2 78 13.2 11.9 2975.82 8 3 79 13.0 12.4 2839.38 11 4 84 14.2 13.3 3136.58 15 5 77 11.4 11.2 2470.50 5 6 82 14.4 13.1 3136.58 9 7 82 13.3 12.8 2799.55 8 8 75 12.4 11.9 2565.50 6 9 81 10.7 11.5 2429.49 11 10 71 7.6 7.8 2369.37 6 11 77 11.2 10.8 2644.62 7 12 74 9.7 9.7 2647.45 9 13 77 10.2 10.0 2672.92 7 14 74 10.1 9.7 2640.25 8 15 68 6.1 7.2 1926.60 5