The first constraint
in row 15 requires the total of the weighted input values to
be 1. The coefficients of the first constraint for the outputs
are 0, while the unit input values for the focus DMU are in the
input columns. (18 in this case). This constraint is an equality
as indicated by the "=" in E15. The remaining constraints
are derived from the efficiency limitations that require the
ratio between inputs and outputs be less than or equal to 1.
The buttons on the LP model worksheet control the Math Programming
add-in. They can be used to add constraints or variables to
the model. Clicking the Solve button solves the current model.
For Croydon, the solution determines the weights that maximize
the efficiency for Croydon. The objective value in F4 is the
DEA efficiency.
The LP model for Reigate is shown below. To get a new focus
DMU simply enter its index in I2. The coefficients of the objective
function and first constraint change, but all other LP data
remains the same. |