Correlation Coefficient Computation Guide

Correlation Coefficient Computation

Data Points

  • X Values:

    • 9
    • -4
    • 2
    • 37
    • 4
    • 27
    • -5

  • Y Values:

    • 9
    • 12
    • 3
    • 16
    • 0
    • 26
    • 20
    • 20

Tools Used

  • Excel: The first option given is to send the data to Excel for analysis. Excel can compute the correlation coefficient using the following formula:

    • The correlation coefficient formula in Excel is:
    • =CORREL(array1, array2)
    • Where array1 is the range of X values and array2 is the range of Y values.

  • TI-84 Plus Calculator: Alternatively, one can use the TI-84 Plus calculator. The steps to calculate the correlation coefficient (denoted as ( r )) are as follows:

    1. Enter the X and Y data in two lists, typically L1 and L2.
    2. Navigate to the Stat menu.
    3. Select Calc and then LinReg(ax+b).
    4. The correlation coefficient ( r ) is displayed among other regression outputs.

Final Steps

  • After calculating, ensure to round the answer to at least three decimal places.
    • For example, if the output of the correlation coefficient is found to be ( r = 0.8765 ), round it to ( r = 0.877 ).

Result Expected

  • The final correlation coefficient is:
    • ( r = ext{[Your Computed Value]} )

Note

  • If the correlation coefficient calculation does not meet expectations, recheck data entry and computation steps, then try again to ensure accuracy.