Chapter PII, Problem 4RE

(a)

To determine

To explain do you see any evidence of an association.

Answer to Problem 4RE

No, we do not see any evidence of an association.

Explanation of Solution

The scatterplot of the case price in dollars with respect of the size of the vineyard is given in the question. And an outlier of red “ $+$ ”dot is also given in the scatterplot. Thus, no, we do not see any evidence of an association because we do not see any strong association between the case price and the size of the vineyard as the points in the scatterplot are scattered more and does not show any pattern.

(b)

To determine

To explain what concern do you have about this scatterplot.

Explanation of Solution

The scatterplot of the case price in dollars with respect of the size of the vineyard is given in the question. And an outlier of red “ $+$ ” dot is also given in the scatterplot. Thus, by looking at the scatterplot we can see that the concern we have about this scatterplot is that small vineyards have the highest and lowest prices and the outlier in the red plus dot in the right hand corner of the scatterplot.

(c)

To determine

To explain would the correlation become stronger or weaker if the red “ $+$ ”data point is removed.

Answer to Problem 4RE

The correlation would become stronger.

Explanation of Solution

The scatterplot of the case price in dollars with respect of the size of the vineyard is given in the question. And an outlier of red “ $+$ ” dot is also given in the scatterplot. Thus, if the red “ $+$ ”data point is removed then the correlation would become stronger because the line would be closer to the other points in the scatterplot.

(d)

To determine

To explain would the slope of the lineincrease or decrease if the red “ $+$ ”data point is removed.

Answer to Problem 4RE

The slope of the line would increase.

Explanation of Solution

The scatterplot of the case price in dollars with respect of the size of the vineyard is given in the question. And an outlier of red “ $+$ ” dot is also given in the scatterplot. Thus, if the red “ $+$ ”data point is removed then the slope of the line would increase because the line would start lower but move towards the high end points.