## 2 Literature Review
### Design Considerations for Collaboration in IVR  
By searching the existing literature on collaboration design, we identified four key design considerations for IVR spaces supporting effective collaboration, as summarized in Table 1. The first is role script design. Considering the imaginative features of VR, designers can create vivid and diverse function avatars and establish rules that encourage multiple learners to collaborate toward a shared goal [50]. For example, [PERSON] et al. [51] developed a Cellverse virtual space, established roles (explorers and navigators), and distributed resources between players. The explorers were responsible for completing tasks that involved identifying protein structures and tracking processes within the cell, and the navigators guided the explorers and provided helpful clues for working with other team members. This sharing of responsibilities in design builds positive interdependence and individual accountability between team members. The second is task design. As emphasized by [PERSON] et al. [54] and [PERSON] et al. [1] regarding the characteristics of the IVR story structure, multiuser collaborative tasks should be narrative-driven, attractive, and challenging to engage users emotionally and intellectually in common objectives. For instance, [PERSON] et al. [11] constructed a VR forest environment where students could roam freely, see three forest animals, and learn their typical characteristics. This IVR task demonstrated an authentic and interesting virtual scenario to attract users to find animals located in different areas. However, the approach of introducing the characteristics of animals mainly focused on content in a direct presentation, lacking challenge and exploration. The third is collaboration mechanism design. This principle refers to design content and instructions that are equally accessible to all users [50]. This can be achieved through task design, role design, or by allowing students to collaboratively discuss strategies. Several studies have been designed to allow collaborators to access the VR world through different devices [14; 50]--for example, two collaborators who physically stayed in the same space, one of them wearing an HMD and the other using a tablet to experience VR separately. However, there existed unequal involvement among students because these IVR collaboration rules allowed one to experience a highly immersive virtual world and the other merely to access information through a 2D or 3D flat screen, which potentially influences effective and worthwhile collaboration. The fourth is feedback and communication mechanism design. This involves integrating virtual space feedback design with real-time communication design while aligning real and virtual locomotion. This aligns with the \"actional\" and \"social\" features of IVR-based learning environments proposed by [PERSON] et al. [55]. [PERSON] et al. [18] established a 360\({}^{\circ}\) panoramic virtual learning space for masonry and architectural knowledge learning, where students can use their keyboard and mouse interfaces to direct a color-coded virtual laser pointer. This IVR space enabled students to point to 360\({}^{\circ}\) panoramic content while \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Collaboration Design Principle** & & **Description** & **References** \\ \hline Role script design & \(\bullet\) & create vivid and diverse function avatars & [50; 51] \\ \(\bullet\) & establish rules that encourage learners to collaborate & & \\ \hline Task design & \(\bullet\) & narrative-driven & [1; 11; 54] \\  & \(\bullet\) & attractive & \\  & \(\bullet\) & challenging & \\ \hline Collaboration mechanism design & \(\bullet\) & equal access in virtual world for all users & \\  & \(\bullet\) & permit collaboratively discussing strategies & [14; 50] \\ \hline Feedback and communication design & \(\bullet\) & provide virtual space feedback & [18; 55] \\  & \(\bullet\) & allow real-time communication & \\ \hline \hline \end{tabular}
\end{table}