The thing I don't understand is how does finding out the median help you drawing in the horizontal and vertical lines. How do you know if it's going to pass through a few of the data points? Like in the example on that website it has a moderate negative correlation and the median is the 8'th score. How did they put the vertical+horizontal line by knowing the median? I see 6 data points in the B quadrant, 5 in the D quadrant, 1 in both A and C. How did they know all this by just the 8'th score? Thanks.