
Related Lists and 1-Dimensional Data Sets 135
FIGURE 6.6
Scatter plot of the two elevation data sets, at the equator and 5” north of it.
A one-to-one positive correlation is ma rked by a solid grey line.
are ab ove their respective means or below their respective means together.
When one is above its mean and the other is below, negative cor relation is
credited.
The Pearson correlatio n coefficient is normalized to vary between −1 and
1, with 1 representing perfect correlation (a positive relationship), and −1
representing perfect anti-correlation (a negative relationship). If ρ is 0, then
no correlation has been revealed by this statistic. Since actual ...