Question:
One of the measures of the effectiveness of a stimulus is how much the viewer’s pulse rate increases on exposure to it. In testing a lively new music theme for its television commercials, an advertising agency shows ads with the new music to a sample of 25 viewers. Their mean pulse rate increase is 20.5 beats per minute, with a standard deviation of 7.4. For a comparable sample of 25 viewers seeing the same ads with the previous music theme, the mean pulse rate increase is 16.4 beats per minute, with a standard deviation of 4.9. Assuming normal populations and using the 0.025 level of significance, can we conclude that the new music theme is better than the old in terms of increasing the pulse rate of viewers? What is the most accurate statement that could be made about the p-value for this test?