Based on the information from the scatter plot, you decide to modify your study by changing your measure of arousal. Instead of heart rate, you now assess arousal through multiple measures of sympathetic nervous system activity. You calculate a Total score of arousal for your participants, Which is measured on a ratio scale. Your scatter plot now looks more like this:

SCATTER PLOT 3.5 3 > 25 2 1.5 100 his 200 300 400 500 X