## 3 Materials and Methodology
### Data Source
\begin{table}
\begin{tabular}{l l l l l l} \hline \hline
**Category** & **Variable** & **Frequency** & **Category** & **Variable** & **Frequency** \\ \hline Organizational influences & Insufficient device (O1) & 13.24\% & Seafarers’ unsafe acts & Inadequate handover (U1) & 1.68\% \\  & Lack of operation certificate (O2) & 2.73\% & & Failure to use protective & 2.94\% \\  & Insufficient education and & & Failure to keep navigational & 2.31\% \\  & training (O3) & 30.88\% & & Requirement in working state (U3) & 2.31\% \\  & Insufficient manning (O4) & 15.97\% & & Insufficient manning on & 8.82\% \\  & Poor competence (O5) & 23.53\% & & Failure to take safety measures in & 0.42\% \\  & Poor information transmission of & 1.05\% & & Failure to perform safety duties & 3.36\% \\  & the company (O6) & 12.39\% & & Drinking/Alcoholism (U7) & 2.31\% \\ Unsafe supervision & Lack of route plan review (S1) & 1.89\% & & OOW (officer on watch) falls & 4.20\% \\  & Lack of supervision and & 29.41\% & & Violation of operational procedures (U9) & 4.62\% \\  & Navigation beyond authorized & & Failure to check the course and & 5.04\% \\  & areas (S3) & & Failure to check the planned route & 1.47\% \\  & Inadequate safety & & Failure to avoid (U11) & 0.42\% \\  & management (S4) & 41.81\% & & Failure to avoid (U12) & 0.42\% \\  & Insufficient maintenance (S5) & 11.13\% & & Severity error (duty sail) & 0.42\% \\  & Inappropriate route plan (S6) & 4.20\% & & Insufficient use of navigational equipment (U13) & 7.35\% \\  & Cargo defect (S7) & 5.25\% & & Over-reliance on navigational equipment (U14) & 2.10\% \\  & Failure to correct mistakes (S8) & 2.73\% & & Failure to exhibit proper light & 2.10\% \\  & Ignore rules and regulations (S9) & 4.41\% & & Failure to make proper sound and & 9.24\% \\ Precondition for & Poor communication between & ships (P1) & 13.03\% & & Failure to maintain proper & 48.32\% \\ unsafe acts & Poor communication & & Failure to control the ship & 13.03\% \\  & (ship-shore) (P2) & 2.52\% & & Failure to control the ship & 13.03\% \\  & Poor team communication (P3) & 13.03\% & & Improper selection of anchoring & 1.68\% \\  & Insufficient utilization of bridge & & Improper emergency response & & \\  & resources (P4) & 5.04\% & & Improves (U20) & 16.81\% \\  & Inadequate preparation (P5) & 1.26\% & & Ignore alarm signals & 0.42\% \\  & Poor physical condition (P6) & 0.42\% & & Failure of seafers to follow best practices (U22) & 1.26\% \\  & Poor emotional state (P7) & 1.26\% & & Failure to execute the planned route (U23) & 1.89\% \\  & Stress (P8) & 0.21\% & & Unsafe speed (U24) & 20.17\% \\  & Alcohol/Drugs (P9) & 1.05\% & & Failure to take effective collision avoidance action early (U25) & 27.94\% \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Descriptive statistics of the seafarers’ unsafe acts and their influencing factors. \begin{table}
\begin{tabular}{l l l l l} \hline \hline
**Year** & **Collision** & **Grounding** & **Contact** & **Sinking** & **Fire/Explosion** \\ \hline
2011 & 5 & 8 & / & 1 & 1 \\
2012 & 3 & 5 & / & 2 & 4 \\
2013 & 2 & 11 & / & 4 & 1 \\
2014 & 8 & 4 & 2 & 4 & 2 \\
2015 & 47 & 11 & 6 & 4 & 5 \\
2016 & 41 & 15 & 9 & 9 & 8 \\
2017 & 39 & 12 & 10 & 4 & 3 \\
2018 & 56