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arXiv · 2011.03461

Defining rough sets as core-support pairs of three-valued functions

Jouni Järvinen·Sándor Radeleczki
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Abstract

We answer the question what properties a collection $\mathcal{F}$ of three-valued functions on a set $U$ must fulfill so that there exists a quasiorder $\leq$ on $U$ such that the rough sets determined by $\leq$ coincide with the core--support pairs of the functions in $\mathcal{F}$. Applying this characterization, we give a new representation of rough sets determined by equivalences in terms of three-valued {\L}ukasiewicz algebras of three-valued functions.

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Jouni Järvinen, Sándor Radeleczki. 2020-11-06. Defining rough sets as core-support pairs of three-valued functions. https://doi.org/10.1016/j.ijar.2021.05.002

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