Final answer:
The symbol for the correlation coefficient is represented by the small letter "r", which measures the strength and direction of the linear relationship between two variables, with values ranging from -1 to +1.
Step-by-step explanation:
The symbol for the correlation coefficient is represented by the small letter "r". This statistic, r, measures the strength and direction of the linear relationship between two variables on a scatter plot. When r is a positive number, it indicates that as one variable increases, the other variable tends to increase as well. Conversely, a negative r value indicates that as one variable increases, the other tends to decrease. The value of r ranges between -1 and +1, with values closer to -1 or +1 indicating a stronger linear relationship, and values near 0 indicating a weaker relationship.
If we have a situation where the correlation coefficient is 0.9, this would suggest a strong positive relationship between the variables, meaning they move together in the same direction. On the other hand, an r value of -0.3 would suggest a weak negative relationship. Additionally, the coefficient of determination, r2, can be used to express the percentage of the variance in one variable that is predictable from the other variable.