Mathematical model A set of voters v=v1,v2,V3,.,ng a set of alternatives or outcomes S=s1, S2, S3,... Sm, with s=m; and A set of preference relation P=R1, R2, R3.Rn, called a preference profile, the preference relation Ri for each voter i is a permutation(order) of elements in S• A set of voters V={v1,v2,v3,…,Vn} • A set of alternatives or outcomes S={s1,s2,s3,…Sm}, with |S|=m; and • A set of preference relation P={R1,R2,R3…Rn}, called a preference profile, – the preference relation Ri for each voter i is a permutation (order) of elements in S. Mathematical model