## 3 Materials and Methods
### Questionnaire Design and Validation
#### 3.3.1. ARI Questionnaire  
The ARI (Augmented Reality Immersion) questionnaire is a 21-item, seven-point Likert-type scale (1 = \"totally disagree\" to 7 = \"totally agree\") designed to measure immersion in location-based AR environments [19]. The questionnaire is grounded in the theoretical framework proposed by [PERSON] and [PERSON] [31], which conceptualizes immersion as a three-level process: engagement, engrossment, and total immersion, originally based on digital game experiences. [PERSON] and [PERSON] [19] adapted this framework for location-aware AR settings, structuring the measurement of immersion into three levels: Engagement, Engrossment, and Total Immersion, each with specific subcategories. Total Immersion includes \"Presence\" and \"Flow\". Presence, as a construct, has often been defined in broad terms, such as \"the feeling of being there\" in a digital environment, which implies a sense of deep involvement [50]. In terms of AR, it implies the sensation of being surrounded by an intertwined real and virtual environment. Flow was originally defined as a profound sense of concentration where the boundaries between reality and the activity blur, making it feel like the only thing that matters [51]. It refers to a condition in which individuals are fully immersed in an activity, maintaining intense focus while ignoring distractions.  
Engrossment covers \"Emotional Attachment\", measuring the user's emotional connection to the AR experience and \"Focus of Attention\", examining the user's concentration on the AR experience. Engagement addresses \"Interest\", which implies the user's curiosity and enthusiasm and \"Usability\", as the ease of interaction with the AR application. Each level and subcategory are evaluated through specific items that collectively assess immersion in AR experiences. It has been widely employed to measure immersion in various AR scenarios, including AR games evaluating cognitive functionality [52], and studies exploring the link between immersion and learning outcomes in AR learning environments [36; 53], which demonstrated that higher immersion levels enhance learning outcomes environments [36]. Although originally developed for AR contexts, the ARI questionnaire has also been applied successfully to assess immersion and user experience in VR and non-VR games [33].  
[PERSON] and [PERSON] [19] noted that the ARI questionnaire has been successfully validated for use in location-aware AR applications in both learning and entertainment contexts, while suggesting that future research could explore its application in other AR types, such as image-based AR emphasizing 3D object augmentation and manipulation. To adapt the questionnaire for a markerless AR application focused on 3D model augmentation, we  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Analysis** & **Q. No.** & \
\begin{tabular}{c} **Research Question-** \\ **naires/Questions** \\ \end{tabular} & **Answers** & **Objective** \\ \hline \multirow{6}{*}{
\begin{tabular}{c} Users’ preferences \\ \end{tabular} } & \multirow{3}{*}{RQ 4} & Choose three sculptures that you prefere the most. & Multiple-Choice (Three Answers) & To evaluate users’ preferences over particular sculptures in order to evaluate users’ attitudes towards digital vs. real-world art in AR. \\ \cline{2-5}  & & & Multiple-Choice (Single-Answer): 1. static (one location—one \\  & & & sculpture or group of sculptures \\ \cline{2-5}  & & & permanently) & To evaluate users’ attitudes towards static vs. dynamic art presentation in AR. \\ \cline{2-5}  & & & location—changeable sculpture or group of sculptures \\ \cline{2-5}  & & & periodically) & \\ \hline \hline \end{tabular}
\end{table}
Table 2: _Cont._developed a modified version of the ARI questionnaire. The design and validation of the proposed questionnaire are detailed in the following section.