## 5 Discussion  
This study began with an analysis of AIS data, which were used to reconstruct specific multi-ship encounter scenarios identified during the risk assessment phase, as illustrated in Figure 4. Stress was evaluated through three instruments--the PSS, HRV, and NASA  
Figure 9: Boxplot of NASA-TLX frustration scores by CoC group. TLX. The participant pool consisted entirely of male officers due to availability constraints at the training facility, while we ensured a sample balance across age and experience. Specifically, 50% of the participants were below 40 years of age and 50% above, while their experience levels were distributed among the low, moderate, and high categories. Although this demographic composition reflects realistic crew compositions in Indonesian merchant marine training institutions, we acknowledge that the gender imbalance may limit the generalizability. This limitation will be addressed as part of our future research recommendations, as well as with added imaginary scenarios that put seafarers in no-way-out situations (for example, an inevitable grounding or collision, where we then add a man overboard situation to see how different groups of seafarers would cope). The significant difference in PSS scores between the younger and older participants suggests that age may influence how stress is perceived. Younger individuals may be more sensitive to stress or experience it more intensely, potentially due to psychosocial or environmental factors such as work demands, educational pressures, or life transitions. Further research is warranted to investigate the underlying mechanisms driving these age-related differences in perceived stress. Similarly, an individual's experience level also appears to play a nuanced role in their perceived stress. The observation that stress perceptions differ significantly between low and moderate experience groups but not between moderate and high experience groups indicates that perceived stress may decrease as individuals gain familiarity with tasks and responsibilities. Specifically, the significant difference observed between the low-experience (group 1) and moderate-experience (Group 2) participants may imply that individuals with little experience are more prone to stress due to their unfamiliarity with operational contexts, a finding that aligns with [55]. Conversely, those in the moderate-experience group may have adapted to their roles, leading to more manageable stress levels. The absence of significant differences between the moderate- and high-experience groups suggests that perceived stress levels may plateau after a certain threshold of experience is reached. These patterns are further supported by exploratory results from non-parametric pairwise comparisons, which provide additional descriptive insights. Although the Kruskal-Wallis test did not reveal overall statistical significance, the comparison between group 1 and group 2 yielded a test statistic of \(-9.846\) and a \(p\)-value of 0.027 (uncorrected), suggesting a potential difference worth further investigation. However, due to the elevated risk of type I errors in this exploratory setting, these findings should be interpreted cautiously and are not considered confirmatory statistical evidence. This study supports the role of sympathetic dominance in high-stress conditions, as reflected in elevated LF/HF values across segments 1, 2, and 5 (Figure 8). These findings reinforce the physiological plausibility of subjective stress assessments in simulator environments. Building on this, regression analyses were conducted to explore how physiological variables predict subjective workload dimensions. The results highlight the protective role of age and the strong influence of ANS markers, such as LFHF2 and MRR2, in stress perception. The results suggest that physiological indicators may play a more dominant role in stress modulation than subjective cognitive demands.