Pearson Correlation Coefficient (r)

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Example: five students studied 1, 2, 3, 4 and 5 hours for an exam and scored 52, 58, 65, 70 and 80. How strong is the relationship between hours and score? Change the values to work out your own case.

Values of x One value per observation, separated by spaces or commas. Values of y In the same order as the x values.

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What each term means

Pearson Coefficient (r): Measures the strength and direction of the linear relationship between two variables. It ranges from -1 (perfect negative correlation) to +1 (perfect positive correlation).
Covariance of X and Y: Measures how two variables change together. It is the numerator of the formula.
Standard Deviation of X: Measures how spread out the values of X are around their mean.
Standard Deviation of Y: Measures how spread out the values of Y are around their mean.