EXAMPLE 7 Calculating Correlation

Table 6.5 gives the SAT Math and Critical Reading scores for five randomly chosen students entering a college.

Table 6.5: TABLE 6.5 SAT Math and Critical Reading Scores
Math SAT, Critical Reading SAT,
610 550
440 410
550 520
520 540
420 410

Next, we walk through the steps of calculating the correlation between the SAT Math and Critical Reading scores.

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  • Step 1. Calculate the mean and standard deviations:

  • Step 2. Calculate the standardized scores for each observation by subtracting the mean and dividing by the standard deviation:
  • Step 3. Substitute into the formula: