Chapter 7, Problem 4CT

(a)

To determine

To find: Whether the given statement is always, sometimes. Or never true.

Answer to Problem 4CT

It is always true.

Explanation of Solution

Given:

The sum of marginal relative frequencies in the total row and the total column of two ways table should be equal to $1$

Concept used:

A marginal relative frequency can be calculated by dividing a row total or a column total by the grand total.

Calculation:

It is always true that the sum of the marginal relative frequencies in the total row and the total column should be equal to $1$ .

Hence, it is always true.

(b)

To determine

To find: Whether the given statement is always, sometimes. Or never true.

Answer to Problem 4CT

It is sometimes true.

Explanation of Solution

Given:

In box and whisker plot, the length of the box to the left of the median and the length of the box to the right of the median are equal.

Concept used:

For the symmetric distributions, the mean is approximately equal to the median and right tails are equally balanced meaning that they have about the same length.

If the right whisker is longer than the left whisker, the distribution is positively skewed.

Calculation:

Sometimes true in this case, the distribution is symmetric. Note that there are many cases where one whisker is longer than the other.

Hence, it is sometimes true.

(c)

To determine

To find: Whether the given statement is always, sometimes. Or never true.

Answer to Problem 4CT

It is sometimes true.

Explanation of Solution

Given: Qualitative data are numerical.

Concept used:

Qualitative or categorical data have no logical order, and can’t be translated into a numerical value.

Quantitative or numerical data are numbers, and that way they imposed an order.

Calculation:

It is sometimes true that the example in the discussion, jersey numbers or uniforms are numerical but are not quantitative since, it cannot compare or measure them.

Hence, it is sometimes true.