Investigators at an agricultural research facility randomly assigned equal numbers of chickens to be housed in two rooms. In one room a group of chickens experienced normal day/night cycles, while in the other room lights were left on 24 hours a day to see if those chickens would lay more eggs. After collecting data for several days the researchers tested the hypothesis H₀: µ₁ - µ₂ = 0 against the one-tail alternative and found P = 0.22. Which is true?
A) None of these
B) The chickens in the lighted room averaged 0.22 more eggs per day
C) There's a 22% chance that chickens housed in a lighted room produce more eggs.
D) There's a 22% chance another experiment will give these same results.
E) There's a 22% chance that there's really no difference in egg production.

Question

Quizplus · Accepted Answer

The p-value of 0.22 indicates the probability of observing the data (or more extreme) assuming the null hypothesis is true. It does not directly indicate the average difference in egg production, the probability of a specific outcome in future experiments, or the probability that there's no difference in egg production.

Investigators at an Agricultural Research Facility Randomly Assigned Equal Numbers