Safety assessment for inland waterway transportation with an extended fuzzy TOPSIS

Maritime safety has been one of the top concerns for inland waterway transportation, and safety assessment based on historic accident data is one of the most effective ways to evaluate navigation risk and take steps to enhance safety. Maritime safety is usually affected by many cost/benefit indicators, and it can be treated as multi-criteria decision making problem. An extended technique for order preference by similarity to ideal solution is proposed in this article at first. The model not only facilitates the comparison between fuzzy numbers with the same expected value but also makes it possible for the fuzzy number with lower expected value but higher reliability to outperform that with higher expected value but lower reliability. A variance matrix is adapted to measure the degree of uncertainty of an alternative. The proposed method is then applied to an inland waterway transportation safety assessment, which is regarded as a multi-criteria decision making. The results indicate that the safety situation has been improved a lot over the last 21 years with some local fluctuations, and an evident improvement can be seen from the year of 2003. In addition, the extended model is proved to provide more flexibility for the ranking of alternatives with similar expected values.