Question: In the Preview section of this chapter, we discussed a report describing how the accuracy of Olympic marksmen can be affected by heartbeats. Pelton (1983) reported that Olympic-level marksmen shoot much better if they fire between heartbeats rather than squeezing the trigger during a heartbeat. The small vibration caused by a heartbeat seems to be sufficient to affect the marksmen's aim. The following hypothetical data demonstrate this phenomenon. A sample of n = 8 Olympic marksmen fire a series of rounds while a researcher records heartbeats. For each marksman, the total score is recorded for shots fired during heartbeats and for shots fired between heartbeats. Do these data indicate a significant difference? Test with a = .05.