There are five variables in the dataset, and all are included in the scatterplot matrix shown in Figure 2.102. The graph shows scatterplots for each pair of quantitative variables, with the Type categorical variable included on each. For example, the second one down on the left is the same scatterplot as in Figure 2.101(b), with petal width on the horizontal axis and petal length on the vertical axis. 

(a) Which shows a clearer distinction between Versicolor and Virginica: a scatterplot of petal length and petal width or a scatterplot of sepal length and sepal width? 

(b) Considering only the Setosa type of iris, does the association between sepal width and petal length appear to be positive, negative, or neither?

Transcribed Image Text:

Petal Length 70 60- 50 20 T 10 T T T T :||!·· 5 • • · 10 15 Petal Width (a) Figure 2.101 Petal length and petal width .. 20 . 25 Petal Length 70 60 40 30 20 10 O 5 10 15 Petal Width (b) 20 25 Type Setosa Versicolor Virginica