An outranking approach for multi-criteria decision-making problems with simplified neutrosophic sets.

•The novel operations of simplified neutrophic numbers (SNNs) and relational properties are developed.•Some outranking relations for SNNs are defined based on ELECTRE, and properties among the outranking relations are further discussed in detail.•Based on the outranking relations of SNNs, the ranking approach is developed to handle MCDM problems.