If data set a of (x, y) data has correlation coefficient r = 0.65, and a second data set b has correlation r = –0.65, then
(a) the points in a exhibit a stronger linear association than b.
(b) the points in b exhibit a stronger linear association than a.
(c) neither a nor b has a stronger linear association.
(d) you can’t tell which data set has a stronger linear association without seeing the data or seeing the scatterplots.
(e) a mistake has been made—r cannot be negative.