For each calculation problem in Questions 3 to 5,

determine the appropriate test (from the list of four listed in Question 2 above);

state the null hypothesis symbolically;

state the research hypothesis symbolically (being sure to determine if the alternative

hypothesis should be directional or nondirectional),

show the appropriate formula, your substitutions, and your obtained value;

state what the critical value(s) is/are;

state your decision with respect to the null hypothesis (reject the null or fail to reject

the null), and

state your conclusion in words, including the APA formatted t statement.

Example 1: Section B's average MT1 FIB score (M = 79.22, s = 12.39) was significantly higher than Section A's average (M = 75.76, s = 10.43), t(290) = -1.99, p < .05. Example 2: This sample's mean creativity score of 83.98 (s = 8.76) did not differ significantly from the population mean of 72.67 for all 19-23 year-olds, t(34) = 0.83, ns.

Unless otherwise stated, assume that alpha is set at .05, and that the population is normally distributed. For independent samples t-test problems, use non-pooled variances.

3. Researchers hypothesized that school-aged children under stress give what they perceive to be more socially desirable answers on an angst measure than normal children do, resulting in lower angst scores. For the data on the 36 children under stress the mean angst score was 11.00, with a standard deviation of 6.99. The population mean angst score for school-aged children on this measure is reported as 15.45. Do the stressed children report significantly lower levels of angst than children in the general population? [If this is an independent samples t-test problem, use non-pooled variances]

Appropriate test?

H0

H1

Formula, substitution, and obtained value:

Critical value(s)?

Reject or fail to reject the null hypothesis?

Conclusion in words?