Answer the following questions after reading the article below:

1. Managerially differences in numbers may be useless?
2. Do differences in numbers mean things are significantly different?

Take a customer satisfaction rating of 3.9. If you implemented a program to improve customer satisfaction, conducted some polling several months out to test the program's effectiveness, and found a new rating of 4.1, has your program been a suc- cess? Not necessarilyyou have to check the confidence interval. In this case, 4.1 might not be statistically different from 3.9 because it fell within the confidence interval. In other words, you could have no more confidence that 4.1 is the real customer rating than you could that 3.9 is correct.

Because they're unaware of how confidence intervals work, managers tend to overcelebrate and overpunish. For example, a VP might believe the 4.1 rating indicates a gen- uine improvement and award a bonus to the manager who launched the new customer satisfaction program. Six months later, when the number has dropped back to 3.9, he might fire the manager. In both instances, the VP would be making decisions based on statistically insignificant shifts in the data.