An operations researcher investigated whether the type of digital inventory system affects the speed of order fulfilment in a major distribution warehouse. They designed an independent measures study comparing a newly introduced Augmented Reality (AR) Headset system to the traditional Handheld Scanner system. The researcher recorded the time taken (in minutes) by 20 randomly allocated workers to locate and retrieve a standard batch of items.
The results, alongside their overall ranks, are presented in the table below.
| Time taken (minutes) by workers using the AR Headset system compared to those using the Traditional Handheld Scanner | Traditional Handheld Scanner | ||
|---|---|---|---|
| AR Headset | Traditional Handheld Scanner | ||
| Time (mins) | Rank | Time (mins) | Rank |
| 12 | 4.0 | 18 | 13.5 |
| 15 | 8.5 | 22 | 18.0 |
| 11 | 2.0 | 17 | 12.0 |
| 14 | 7.0 | 25 | 20.0 |
| 13 | 6.0 | 19 | 15.0 |
| 16 | 10.5 | 21 | 17.0 |
| 10 | 1.0 | 16 | 10.5 |
| 15 | 8.5 | 24 | 19.0 |
| 12 | 4.0 | 20 | 16.0 |
| 12 | 4.0 | 18 | 13.5 |
Calculate the mean retrieval time for each condition. Show your workings.
513 exam-style questions on OCR A Level Psychology Data recording, analysis and presentation. Each one has a worked solution and a mark scheme showing where the marks go.