The data from Exercise 7 in Chapter 7 are reproduced in the following table. Calculate the mean and the unbiased standard deviations for both the experimental and control groups, and then compute the Pearson r with the raw-score formula that uses the s's rather than the σ's in its denominator. Is the correlation coefficient significant? Given your decision with respect to the null hypothesis, what type of error could you be making, Type I or Type II? (Advanced exercise: Recompute the matched-pairs t test with the formula that is based on Pearson's r, and compare it to the t value you calculated for these data in the previous chapter.)

Data from exercise 7(chapter 7)

Test the results for statistical significance at the .05 level. What should the psychologist decide about his or her new programmed text?

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Experimental group||Control group| Pair (programmed text) (standard text) 4 5 14 15 3 3 3 2 18 4 5 19 6 10 10 3. Experimental group||Control group Pair (programmed text) (standard text) 3 5 4 5 3 4 15 6. 10 10 6. 3. 3. 3.