What does the correlation coefficient “R” mean?
R indicates the strength and direction of the correlation. Look at the above graph of “income and years of education”. The coefficient is +.79. Since it is positive in means that higher incomes are related to higher education, and lower incomes to lower education. The correlation is positive because they both move in the same direction which results in an upwardly sloping line. If there were a perfect +1 correlation all of the dots would fall exactly on the line. This would mean that every year of education would be related to exactly a certain dollar amount in salary. Exact correlations are not often found in behavioral studies, but are in nature. For example, if you filled a container with water and weighed it, the weight of the water is perfectly correlated with the weight of the water; all of the volume and weight dots would be on the line. A negative correlation occurs on the “GPA and hours of TV graph” (-.63). It is negative because more TV is correlated with a lower GPA, and a h
