# A Comparative Study of Design Evaluation with Virtual Prototypes Versus a Physical Product
## 3 Results and Discussion
### Providing Feedback
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & \multicolumn{4}{c}{(**a**)} \\ \hline
**Source** & **DF** & **Adj SS** & **Adj MS** & **F** & **P** \\ \hline Regression & 10 & 103.240 & 10.3240 & 0.445 & 0.000 \\ Virtual versus Physical & 4 & 53.566 & 13.3915 & 5.57 & 0.000 \\ Error & 179 & 430.702 & 2.4062 & & \\ Pure Error & 116 & 249.247 & 2.1487 & & \\ Total & 189 & 533.942 & & & \\ \hline \multicolumn{4}{c}{(**b**)} \\ \hline
**Term** & **Coef** & **SE Coef** & **T** & **P** & **VIF** \\ \hline Constant & 3.79 & 1.02 & 3.72 & 0.000 & \\ \hline \multicolumn{4}{c}{**Virtual versus Physical**} \\ \hline
**-3** & 0.693 & 0.446 & 1.55 & 0.122 & 2.09 \\ \(-2\) & 0.949 & 0.419 & 2.27 & 0.025 & 1.84 \\ \(-1\) & 1.683 & 0.650 & 2.59 & 0.010 & 6.47 \\
1 & 0.509 & 0.711 & 0.72 & 0.475 & 7.73 \\ \hline \hline \end{tabular} SS: Sum of squares; DF: Degrees of freedom; MS: Mean square. VIF: Variance inflation factor.  
\end{table} 
Table 10: (**a**) ANOVA for the valence construct of the dirt-offloading task with different feedbacks. (**b**) Multiple comparisons of the valence construct for integrated feedback. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & \multicolumn{4}{c}{(**a**)} \\ \hline
**Source** & **DF** & **Adj SS** & **Adj MS** & **F** & **P** \\ \hline Regression & 10 & 81.603 & 8.1603 & 2.43 & 0.010 \\ Virtual versus Physical & 4 & 30.030 & 7.5075 & 2.23 & 0.067 \\ Error & 179 & 602.166 & 3.3641 & & \\ Pure Error & 116 & 381.915 & 3.2924 & & \\ Total & 189 & 683.768 & & & \\ \hline \multicolumn{4}{c}{(**b**)} \\ \hline Term & Coef & SE Coef & T & P & VIF \\ \hline Constant & 3.77 & 1.20 & 3.13 & 0.002 & \\ \hline \multicolumn{4}{c}{**Virtual versus Physical**} \\ \hline
**-3** & 0.949 & 0.527 & 1.80 & 0.074 & 2.09 \\ \(-2\) & 0.629 & 0.495 & 1.27 & 0.205 & 1.84 \\ \(-1\) & 1.264 & 0.769 & 1.64 & 0.102 & 6.47 \\
1 & 0.554 & 0.840 & 0.66 & 0.511 & 7.73 \\ \hline \hline \end{tabular} SS: Sum of squares; DF: Degrees of freedom; MS: Mean square. VIF: Variance inflation factor.  
\end{table} 
Table 11: (**a**) ANOVA for the arousal construct of the dirt-offloading task with different feedbacks. (**b**) Comparison of the arousal construct for integrated feedback. an interesting observation was that most participants appeared to be positively surprised when they received feedback. Therefore, sensory feedback may have helped the virtual prototypes mimic the behavior of the actual product to a larger degree. A similar observation was reported in the previous study of product use experience with an integrated with sensory feedback [28]. To test the reliability of the questionnaires, we analyzed the questionnaires collected from the physical and virtual groups with [PERSON]'s Alpha test. The results revealed that the alpha value of the physical group's questionnaires was 0.709, while that of the virtual group was 0.759. The value of all the questionnaires as a whole was 0.718. These numbers indicate the high reliability of the questionnaires and imply good consistency for the responses collected from different participants.