Question

Concussions and Brain Size A recent study1 examined the relationship of football and concussions on hippocampus volume in the brain. The study included three groups with in each group: healthy controls who had never played football, football players with no history of concussions, and football players with a history of concussions. In this exercise, we test for evidence that average brain size is larger in football players who have never had a concussion (FBNoConcuss) than in football players with a history of concussions (FBConcuss). The data are in FootballBrain where the variable Hipp measures brain size as the volume of the hippocampus (in ml) for each subject. Let group be the football players with no concussion and group be the football players with a history of concussions.

Answer 1

Answer:

Part A: Null hypothesis. H₀: M₁ = M₂

Alternative hypothesis, H₁ : M₁ > M₂

Part B: x1-x2 = 6459-5735 = 724

Part C: p-value = 0.000

Part D: No, the difference in brain size is not due to random chance

Explanation:

See attached image