36. Effect of No Variation in Sample An experiment was conducted to test the effects of alcohol. The breath alcohol levels were measured for a treatment group of people who drank ethanol and another group given a placebo. The results are given in the accompanying table. Use a 0.05 significance level to test the claim that the two sample groups come from populations with the same mean. The given results are based on sx2y 2 5 sx 2 1 sy 2

s2 s1 5 s2 s1 5 s2 s1 5 s2 s1 5 s2 s1 5 s2 484 Chapter 9 Inferences from Two Samples data from “Effects of Alcohol Intoxication on Risk Taking, Strategy, and Error Rate in Visuomotor Performance,” by Streufert et al., Journal of Applied Psychology, Vol. 77, No. 4.