ContraSoft Set and ContraRough Set with using Upside-down logic

A Soft Set is a parameterized family of subsets of a universe, where each parameter selects elements relevantunder that condition. A Rough Set is an approximation framework that employs lower and upper sets tocapture definite and possible memberships under an indiscernibility relation. Recent research has exploredextensions of Soft Sets and Rough Sets through concepts such as Hyper, SuperHyper, and Tree structures. Inthis paper, we investigate the ContraSoft Set and ContraRough Set, which enrich Soft Sets and Rough Sets byincorporating the notion of contradiction values. We further examine their mathematical structures, providesimple illustrative applications, and discuss how these constructions can be applied within the framework ofup-side-down logic.