Final answer:
True statements about the correlation coefficient are that it gives us information about the strength of the linear association between two variables (1), the closer the absolute value of r is to 1, the stronger the relationship (3), and that correlation does not imply causation, meaning variables can be correlated without one causing the other (6).
Step-by-step explanation:
The question pertains to the characteristics of the correlation coefficient, commonly denoted as r, and its interpretation in statistical analysis. The correlation coefficient is a measure of the linear relationship between two quantitative variables, and it ranges from -1 to 1. Let's address the statements provided:
- The correlation coefficient gives us information as to how strong the linear association is between two quantitative variables. True.
- The Correlation coefficient has units of measurement and does always lie between -1.0 and +1.0. False, r is unitless and does always lie between -1.0 and +1.0.
- The closer the absolute value of r is to 1, the stronger the relationship is between the two variables. True.
- A correlation coefficient of r=0 indicates a strong linear relationship between two variables. False, r=0 indicates no linear relationship.
- A correlation coefficient of r=-0.9 indicates a weak linear relationship between two variables. False, r=-0.9 indicates a strong linear relationship, but in a negative direction, meaning as one variable increases, the other decreases.
- Two variables can be correlated without one causing the other. True, correlation does not imply causation.
It is essential to remember that a correlation coefficient close to -1 or 1 signifies a strong linear relationship, while a coefficient close to 0 signifies a weak or no linear relationship. The sign of the coefficient indicates the direction of the relationship; positive for a direct relationship and negative for an inverse relationship.