Chapter 13, Problem 81H

Thirty men in college were taught a method of finger tapping. They were randomly assigned to three groups of ten,

with each receiving one of three doses of caffeine: 0 mg, 100 mg, 200 mg. This is approximately the amount in no, one, or

two cups of coffee. Two hours after ingesting the caffeine, the men had the rate of finger tapping per minute recorded. The

experiment was double blind, so neither the recorders nor the students knew which group they were in. Does caffeine affect

the rate of tapping, and if so how?

Here are the data:

0 mg	100 mg	200 mg	0 mg	100 mg	200 mg
242	248	246	245	246	248
244	245	250	248	247	252
247	248	248	248	250	250
242	247	246	244	246	248
246	243	245	242	244	250

Table 13.35