To detect the presence of harmful insects in farm fields, we can put up boards covered with a sticky material and examine the insects trapped on the boards. Which colors attract insects best? Experimenters placed boards of several colors at random locations in a field of oats (four colors and six boards of each color). Here are the counts of cereal leaf beetles trapped by each board:

(a) Make a plot of the number of beetles trapped on each board against the board's color, arranging the colors to show blue first, then white, then green, and last yellow (space the four colors equally on the horizontal axis).

(b) Does it make sense to speak of a positive or negative association between beetles trapped and board color? Why?

(c) Based on your graph, which of the four colors seems to beat attract cereal leaf beetles?