Response to the discussion by Montewka Jaku, Gil Mateusz and Wróbel Krzysztof on the article by Zhang & Meng entitled “Probabilistic ship domain with applications to ship collision risk assessment [Ocean Eng. 186 (2019) 106130]

Abstract This note aims to address the concerns and confusions raised by Jakub et al. (2020) on the article of Zhang and Meng published in Ocean Engineering in 2019. Zhang and Meng (2019) mainly proposed the probabilistic ship domain to capture the diverse navigational behaviors of captains based on the big AIS data with less emphasies on how to assess ship collision risk using the probabilistic ship domain. To achieve of the aim, we first examine two concepts of ideal ship domain and practical ship domain. We proceed to investigate the relationship between ship domain and ship collision risk using field data from restricted water in both Singapore strait and fairway. We finally discuss the onboard collision detection by using the probabilistic ship domain incorporating with the Closest Point of Approach (CPA). This note not only clarifies some confusions or misunderstandings of the applicaion of probabilistic ship domain for ship collision risk assessment bust also exhibits the values and merits of the probabilistic ship domain.