Key Terms

coefficient of correlation
a measure developed by Karl Pearson during the early 1900s that gives the strength of association between the independent variable and the dependent variable;
r=nxy[x][y](nx2[x]2)(ny2[y]2)r=nxy[x][y](nx2[x]2)(ny2[y]2)
where n is the number of data points

 
The coefficient cannot be more than 1 and less than –1. The closer the coefficient is to ±1, the stronger the evidence of a significant linear relationship between x and y.
outlier
an observation that does not fit the rest of the data