Chapter 7, Problem 5E

(a)

To determine

To find out which of the scatterplots given in the question shows little or no association.

Answer to Problem 5E

Scatterplot $4$ and scatterplot $1$ .

Explanation of Solution

Scatterplot $4$ and scatterplot $1$ , if we only consider linear association shows little or no association.

This is because scatterplot $4$ shows some what a negative linear association but it is very weak whereas scatterplot $1$ does not have a linear association but it has a very strong non-linear association. In fact, it has a very strong quadratic association.

(b)

To determine

To find out which of the scatterplots given in the question shows a negative association.

Answer to Problem 5E

Scatterplot $3$ and scatterplot $4$ .

Explanation of Solution

Scatterplot $3$ and scatterplot $4$ shows a negative association.

It is because since scatterplots $3$ and scatterplot $4$ have points in a downward trend. The difference is the former has a very strong association and the latter has a very weak association. Thus, it shows a negative association.

(c)

To determine

To find out which of the scatterplots given in the question shows a linear association.

Answer to Problem 5E

Scatterplot $2$ , scatterplot $3$ and scatterplot $4$ .

Explanation of Solution

Scatterplot $2$ , scatterplot $3$ and scatterplot $4$ shows a linear association.

This is because since they have points either in an upward trend that is scatterplot $2$ or in a downward trend that is, scatterplots $3$ and scatterplot $4$ . The only one that is not linear is scatterplot $1$ . Thus, these three scatterplots shows a linear association.

(d)

To determine

To find out which of the scatterplots given in the question showsa moderately strong association.

Answer to Problem 5E

Scatterplot $2$ .

Explanation of Solution

Scatterplot $2$ shows a moderately strong association.

This is because since it has points in an upward trend and the points are neither too clustered nor too scattered. Thus, the scatterplot $2$ shows a moderately strong association.

(e)

To determine

To find out which of the scatterplots given in the question shows a very strong association.

Answer to Problem 5E

Scatterplot $3$ .

Explanation of Solution

Scatterplot $3$ shows a very strong association.

This is because since it has points in a downward trend and the points are really clustered together. Thus, it shows a very strong association than the other scatterplots given in the question. Thus, scatterplot $3$ has a very strong association.