Rough Set Based Study of the Competency for Chinese Seafarers

On base of current research of the quantitative assessment of competency for Chinese seafarers, aiming at the weakness of fuzzy comprehensive assessment, the rough set theory is introduced into the quantitative studies of competency for Chinese seafarers. Based on the discrete decision table and rough membership degree, some useful data mining results are given: the degree of rough membership is an inverse ratio to seafarer´s age, education extent and sea experiences. For age factor, seafarers within 39 years old have higher membership degree. For education extent factor, middle or less educated seafarers have higher membership degree. For sea experiences, 18 months or less experienced seafarers have higher membership degree. For rank factors, master has high membership degree. High membership degree in watch-keeping time is 0000~0004, whereas low degree occurs in 0012~0016 and 0020~0024.