Question

The weighted voting systems for the voters A, B, C, ... are given in the form q: w1, w2, w3, w4, ..., wn . The weight of voter A is w1, the weight of voter B is w2, the weight of voter C is w3, and so on. Calculate, if possible, the Banzhaf power index for each voter. Round to the nearest hundredth. (If not possible, enter IMPOSSIBLE.) {76: 52, 39, 31, 25, 9}

Answer 1

Banzhaf power index for each voter

Voter A = 3/4 = 0.75

Voter B = 0/4 = impossible

Voter C = 1/4 = 0.25

Explanation:

using the Banzhaf power index for each voter

{76: 52, 39, 31, 25, 9}

Voter A = 52

Voter B = 39

Voter C = 31

Voter D = 25

Voter E = 9

lets calculate the Banzhaf power index for Voters A to C

A B = 52 + 39 ≥ 76

B C = 39 + 31 ≤ 76

A C = 52 + 31 ≥ 76

A B C = 52 + 39 + 31 ≥ 76

Lets consider critical

A B : A is critical because without A the sum < 76

B C : B is not critical because without B the sum is still < 76

A C : C is critical because without C the sum < 76

A B C : A is critical as B + C < 76

B is not critical as A + C ≥ 76

C is not critical as A + B ≥ 76

Number of times critical : For A = 3, For B = 0 , For C = 1

Banzhaf power index for each voter

Voter A = 3/4 = 0.75

Voter B = 0/4 = impossible

Voter C = 1/4 = 0.25