Imagine a scatterplot of a class of 20 students showing the relationship between SAT scores on
the x axis and class grade on the y axis, with 19 of the dots showing a clear positive linear
relationship going from the bottom left to the upper right. However, the 20th student (who scored
very high on the SAT) hasn't been going to class or doing the homework and so is flunking the
class. Thus, that datapoint is by itself in the bottom right hand corner of the scatterplot. What
would be the effect on the correlation between SAT and grades if the slacker dropped the class and
his datapoint was deleted?
A. The correlation coefficient (r) would increase.
B. The correlation coefficient (r) would decrease.
C. The correlation coefficient (r) would not change.
D. It is impossible to know.