Table A2.
Questions about system usability in the questionnaire and statistics of the average scores of the answers to the questions.
| No. | Questions | Min. | Max. | Average Score | Adjusted Average Score * | Standard Deviation |
|---|---|---|---|---|---|---|
| A. Ease of Use | 4.31 | |||||
| 1 | I think the interface of the interactive device is too complicated. (N) | 2 | 5 | 2.04 | 3.96 ** | 0.85 |
| 2 | I think it is easy to use the interactive device. (P) | 4 | 5 | 4.41 | 4.41 | 0.50 |
| 3 | I need repeated explanations to use the interactive device. (N) | 2 | 5 | 1.96 | 4.04 ** | 0.85 |
| 4 | I can learn to use the interactive device quickly like others. (P) | 4 | 5 | 4.52 | 4.52 | 0.51 |
| 5 | I think it troublesome to use the interactive device. (N) | 4 | 5 | 1.37 | 4.63 ** | 0.49 |
| 6 | I have to learn extra information to use the interactive device. (N) | 2 | 5 | 1.70 | 4.30 ** | 0.67 |
| B. Applicability | 4.26 | |||||
| 7 | I am willing to use interactive device often. (P) | 2 | 5 | 4.15 | 4.15 | 0.82 |
| 8 | I think the functions of the interactive device are integrated well. (P) | 4 | 5 | 4.59 | 4.59 | 0.50 |
| 9 | I think too many inconsistencies exist in the device interface. (N) | 3 | 5 | 1.96 | 4.04 ** | 0.65 |
| 10 | I have enough confidence to use interactive device. (P) | 3 | 5 | 4.26 | 4.26 | 0.71 |
* Adjusted average score = reversed average score = 6 − average score of negative question according to Equation (A2) derived in the following. ** Adjusted average values of negative questions (average scores of positive questions are not adjusted). Underlines emphasize the different computations of the numbers.