Question 6: What conditions or assumptions do the data have to meet for this test to be valid? Do you think they are met here?
For this test to be valid, at least one of the variables must follow a distribution which is approximately Normal.
This is clearly the case for height. Head circumference is slightly skew. We can judge this from the scatter diagram and also from the histograms seen in the Week 1 Exercise: Heights of students and the Week 4 Exercise: Head circumference. (Use the browser's Back button to get back here.)
Back to Exercise: Head circumference and height.
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Last updated: 7 March, 2006.
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