Assertion and reason: choosing a measure

Exercise and reference answers

Questions

1. Reason

   It ignores every observation except the two extremes.

   Verdict

   Both are true; the reason explains the assertion.

   Assertion

   Range alone is a poor description of a data set.

2. Reason

   Taking the square root returns it to the units of the original data.

   Verdict

   Both are true; the reason explains the assertion.

   Assertion

   Standard deviation is reported more often than variance.

3. Reason

   The sum of deviations from the mean is zero.

   Verdict

   Both are true; the reason does not explain the assertion.

   Assertion

   The mean is a measure of central tendency.

Explanation