# Multi-Objective Logging

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## Multi-Objective Logging

The contents of the log for a multi-objective solve will depend on the approach you use to solve the model. As noted in the section on multi-objective models, you have two options. In a blended approach, where the objectives are combined into a single objective, the log will be the same as what you'd see for a single-objective model. When using a hierarchical approach, a series of models is solved, one for each objective priority level. If your model is a pure hierarchical multi-objective problem with three objectives, the optimization process log will start with

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Multi-objectives: starting optimization with 3 objectives ...
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If your model is a mixed hierarchical-blended multi-objective problem with five objectives but only three priorities, the optimization log will start with
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Multi-objectives: starting optimization with 5 objectives (3 combined) ...
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You will also see a log for each solve, introduced by a small header

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Multi-objectives: optimize objective 1 Name ...
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Where Name will be the name of the objective function being optimize, or (weighted) if the objective function is the result of blending more than one objective function.

The logs for the individual solves will again be the same as what you'd see for a single-objective model.