## 4 Results and Discussions  
### Eye Tracking and Keystroke Logging Data Analysis  
Table 2 provides a detailed description of the 10 categorical and continuous variables collected throughout the experiment in both English-to-Chinese (E-C) and Chinese-to-English (C-E) translation directions. These variables were recorded using eye-tracking and keystroke logging technology, capturing key metrics related to fixations, gaze behavior, and pupil dilation. The dataset includes categorical variables such as participant ID, which identifies individual participants, and AU_type, which specifies the translation task being performed (parallel, source text (ST), or Target Text (TT)). Additionally, the dataset contains continuous vari \begin{table}
\begin{tabular}{p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline
**Variable** & **Description** & **Comment** & **Categories** \\ \hline FixationIndex & Unique ID for fixation & [1:936] & - \\ \hline Participant & Unique ID for participant & Factor with 18 levels & P01, P02, P03, P04, P05, P08, P09, P10, P11, P12, P13, P14, P16, P17, P18, P19, P20, P22 \\ \hline AU\_type & The task which is currently being performed & Factor with 3 levels & 1: parallel, 2: source text (ST), 3: target text (TT) \\ \hline FixationPointY (MCSpx) & Point on the screen of gaze along the y-axis & [0:900] & - \\ \hline GazeEventDuration & The amount of time spent gazing at a single point, recorded in (ms) & [0:9500] & - \\ \hline KeyDefinition & The label generated by the eye tracking software & This takes the form of a string & - \\ \hline FixationPointX (MCSpx) & Point on the screen of gaze along the x-axis & [0:1400] & - \\ \hline PupilLeft & The dilation of the left eye pupil & Continuous & - \\ \hline PupilRight & The dilation of the right eye pupil & Continuous & - \\ \hline AVGPupildillation & The average pupil dilation of both pupils & Continuous & - \\ \hline \end{tabular}
\end{table} 
Table 2: Description of variables collected during experimental process. ables related to gaze behavior, including FixationPointX and FixationPointY (screen coordinates of gaze), GazeEventDuration (time spent fixating on a point in milliseconds), and pupil dilation measures (PupilLeft, PupilRight, and their average, AVGpupilidation). Table 3 presents summary statistics for average pupil dilation in both English-to-Chinese (E-C) and Chinese-to-English (C-E) translation directions. Pupil dilation values were obtained by averaging left and right eye pupil measurements, providing a single measure of cognitive effort. The results indicate that the median pupil dilation is slightly lower in C-E translation (2.799) compared to E-C translation (2.853), suggesting potential differences in cognitive load between translation directions. To visualize the distribution of pupil dilation, Figure 2 displays histograms for both translation directions. The distributions exhibit a slight right skew, with a peak around 3.0. This suggests that most pupil dilation values fall within a central range, with higher dilation values appearing less frequently. Instances of elevated pupil dilation may indicate moments of increased cognitive load, potentially due to difficult translation segments or higher processing demands. The presence of extreme dilation values further supports the idea that certain translation tasks induce cognitive overload, requiring increased attentional resources. The boxplots in Figures 3 and 4 provide a broad overview of participant variation in cognitive effort across both English-to-Chinese (E-C) and Chinese-to-English (C-E) translation directions, without distinguishing between AU types. In each boxplot, the dots represent individual data points that fall outside the interquartile range (IQR), indicated by the box, and are referred to as outliers. These points highlight instances where measurements such as pupil dilation or gaze event duration notably deviate from the median (marked by the horizontal line within each box), reflecting moments of particularly elevated or reduced cognitive load during translation tasks.