In 1974, Lotus and Palmer conducted a classic study demonstrating how the language used to ask a question can influence eyewitness memory. In the study, college students watched a filmed of an automobile accident and then were asked about what they saw. One group was asked, questions 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 expect the verb was changed to hit" instead of smashed into" group reported significantly higher estimates of speed than the hit" group. Suppose a researcher repeats this study with a sample of today's college students and obtains the following results.
Estimated Speed
Smashed into Hit
n = 15 n = 15
M = 40. 8 M = 34. 0
SS = 510 SS = 414
2. A researcher conducts an independent -measures research study and obtains t =2.070 with df = 28.
a. How many individuals participated in the entire research study?
b. Using a two-tailed test with α = .05, is there a significant difference between the two treatment conditions?
c. Compute r^2 to measure the percentage of the variance accounted for by the treatment effect.