Final answer:
A. Correlation coefficient
The measurement of the direction and strength of the relationship between two variables is called a correlation coefficient, designated as r. This statistic ranges from -1 to +1, with values closer to the extremes indicating a stronger relationship and values near 0 indicating a weaker relationship. It does not, however, imply causation between the variables.
Step-by-step explanation:
A measurement of the direction and strength of the relationship between two variables is called a correlation coefficient. The correlation coefficient, usually denoted as r, ranges from -1 to +1, indicating the strength and the direction of the relationship between the variables. This statistic is crucial for understanding how variables are related in a linear fashion, but it does not imply causation. The correlation coefficient is calculated using the formula:
nΣ xy -[Σ xΣ y]
√((nΣ x² - (Σ x)²)(nΣ y² - (Σ y)²))
If the correlation coefficient is closer to +1 or -1, the relationship between the variables is stronger. A positive correlation indicates that both variables tend to increase or decrease together, while a negative correlation signifies that as one variable increases, the other decreases, and vice versa. If the correlation coefficient is close to 0, it suggests a weak or no relationship between the variables.