In a study of store checkout scanning systems, samples ofpurchases were used to compare the scanned prices to the posted prices. Theaccompanying table summarizes results for a sample of 819 items. When storesuse scanners to check out items, are the error rates the same forregular-priced items as they are for advertised-special items? How might thebehavior of consumers change if they believe that disproportionately moreovercharges occur with advertised special items?
How do I do a full hypothesis test?
| Regular Price Items | Advertised special items | |
| Undercharged | 20 | 7 |
| Overcharged | 15 | 29 |
| Correct price | 384 | 364 |
Last edited: