Exercise: Head circumference and height, answer 8

Question 8: What conditions or assumptions do the data have to satisfy for this confidence interval to be valid? Do you think these data meet them?

Suggested answer

Both variables must follow an approximately Normal distribution. This is clearly true for height, but not for head circumference, which is slightly skew to the right. Hence the assumptions are not met exactly and the confidence interval may not be quite right.

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Last updated: 7 March, 2006.

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