Question 12: Would we get a different P value if we carried out the regression of height on head circumference?
We get a different line, but the P value is the same.
The regression equation is:
height = 853 + 1.43 × head circumference
This is quite different from the equation
head circumference = 372 + 0.114 × height
which we had earlier. This can be rewritten as
(head circumference - 372)/0.114 = height
height = -372/0.114 + (1/0.114) × head circumference = -3263 + 8.77 × head circumference
which is a much steeper line, as shown on the scatter diagram above.
The P value is <0.001, exactly as we had earlier.
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Last updated: 9 March, 2006.
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