Rough Set Approach to Approximation Reduction in Ordered Decision Table with Fuzzy Decision

Table 4

Lower approximation discernibility matrix 𝑈𝑀_𝑑 of the ODT.

𝑢𝑖,𝑢𝑗	𝑢1	𝑢2	𝑢3	𝑢4	𝑢5	𝑢6
𝑢1	∅	∅	∅	𝑎1,𝑎3	∅	𝑎1,𝑎3
𝑢2	∅	∅	∅	𝑎3	∅	𝑎3
𝑢3	∅	∅	∅	𝑎1,𝑎3	∅	𝑎1,𝑎2,𝑎3
𝑢4	∅	∅	∅	∅	∅	∅
𝑢5	∅	∅	∅	𝑎3	∅	𝑎3
𝑢6	∅	∅	∅	∅	∅	∅