Reducing a
pay-off matrix
A pay-off matrix can be made smaller by eliminating certain
options if a row or column is better (if it dominates).
This can only be done if the row/column is ALWAYS better than
another row/column.
|
B plays 1
|
B plays 2
|
A plays 1
|
7
|
1
|
A plays 2
|
-3
|
6
|
A plays 3
|
4
|
0
|
The 3x2 matrix above can be reduced to a 2x2 matrix.
We can see from the matrix that row 1 dominates row 3; 7 is
bigger than 4 and 1 is bigger than 0. This means that for A no matter what B
does, row 1 is always a better option to play than row 3 hence row 3 can be
eliminated as A would never rationally select it.
Therefore the new deduced matrix would look like:
|
B plays 1
|
B plays 2
|
A plays 1
|
7
|
1
|
A plays 2
|
-3
|
6
|
The same deduction can
be done to a column if another column dominates.
|