Question 14.70

gameranking

28. Video Game Ratings. GameRankings.com publishes summary statistics for reviews of video games. The following data set represents a random sample of video games, with their average reviewer score for the PlayStation 3 platform and the Xbox 360 platform, as of January 23, 2009. Test whether the population median of the differences (PlayStation 3 – Xbox 360) is less than zero, using level of significance .

Game Playstation 3
mean
reviewer score
Xbox 360
mean
reviewer score
Grand Theft Auto IV 0.9373 0.9656
BioShock 0.9403 0.9525
Call of Duty 4 0.9378 0.9416
Rock Band 0.9119 0.9225
The Orange Box 0.8838 0.9624
Guitar Hero III:
Legends of Rock
0.8390 0.8622