Least Absolute Deviations - Solving Methods - Solving Using Linear Programming

Solving Using Linear Programming

The problem can be solved using any linear programming technique on the following problem specification. We wish to

with respect to the choice of the values of the parameters, where yi is the value of the ith observation of the dependent variable, and xij is the value of the ith observation of the jth independent variable (j = 1,...,k). We rewrite this problem in terms of artificial variables ui as

with respect to and
subject to

These constraints have the effect of forcing each to equal upon being minimized, so the objective function is equivalent to the original objective function. Since this version of the problem statement does not contain the absolute value operator, it is in a format that can be solved with any linear programming package.

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