Dr Contrario plans to test conventional wisdom or at least

Dr. Contrario plans to test conventional wisdom – or at least its applicability to early ages – regarding human heights. The following text will refer to lengths instead, because Dr. Contrario was studying 5-month-olds, who are not yet standing.

Dr. Contrario’s assistants measured 12 babies’ lengths, to the nearest inch. They produced the data below. The babies are also sorted in each column by age, so you could think of each row as having the best possible male-female baby pairs for the purpose of similarity.

Dr. Contrario wants to show that, contrary to popular belief, females tend to be longer than males.

If Dr. Contrario\'s assistants perform a sign test, what is the value of the test statistic?

-3.0

1.0

1.5

3.0

Solution

Number of plus signs = 4, Number of minus signs = 1, number of no signs = 1

Hence test statistic x = number of smaller { - sign , + sign ) = 1

Hence correct option is B. 1.0