## APM.EV_TYPE - APMonitor Option

## Main.OptionApmEvType History

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See also Estimation Objective Tuning

See also CV_TYPE, Estimation Objective Tuning

Description: Estimated variable error model type: 1=linear, 2=squared, 3=approximate linear

Description: Estimated variable error model type 1=linear error, abs(model-measured) with slacks 2=squared error, (model-measured)^2 3=approximate linear without slack variables

(:title APM.EV_TYPE - APMonitor Option:) (:keywords APM.EV_TYPE, Optimization, Estimation, Option, Configure, Default, Description:) (:description Estimated variable error model type: 1=linear, 2=squared, 3=approximate linear:)

Type: Integer, Input Default Value: 1 Description: Estimated variable error model type: 1=linear, 2=squared, 3=approximate linear

EV_TYPE applies a specific objective function. Linear is an l1-norm, or in other words the solver minimizes the sum of the absolute value of the difference between the CV and the set point. Squared is an l2-norm or sum squared error (SSE), or in other words the solver minimizes the sum of the squared difference between the CV and the set point. l1-norm can be useful when noise or measurement error is expected because it better rejects those. Option 3 is not typically used as an approximate absolute value function that uses a nonlinear function instead of slack variables.