Answer Happy

In 1974, researchers conducted a classic study demonstrating how the language used to ask a question can influence eyewitness memory. In the study, college students watched a film of an automobile accident and then were asked questions about what they saw. One group was asked, "About how fast were the cars going when they smashed into each other?" Another group was asked the same question except the verb was changed to "hit" instead of "smashed into". The data are in MPH. Use a two-tailed test with alpha=.05. Estimated speed "Smashed into" N=15 M=40.8 SS=510 "Hit" N=15 M-34.0 SS=414 1. Would you retain or reject the homogeneity of variance assumption? What is the test statistic? 2. What is the test statistic for the t-test? Did you retain or reject the null? 3. Compute the 95% confidence interval of the difference. 4. Compute and interpret Cohen's D.