The Heuristics box on the Integer Pre-Solver tab:

controls the level of integer programming heuristics used by the integer solver. These heuristics use the continuous solution at each node in the branch-and-bound tree to attempt to quickly find a good integer solution.

The Level field controls the level and number of heuristics that are applied, and may run from 0 (none) to 100 (highest level.)

The

Criterion is used to control the criterion for terminating heuristics.  Choices here are Solver Decides, Time, and Iterations. Under the Time setting, LINGO terminates heuristics after a certain amount of elapsed time.  The Iterations option terminates heuristics after a certain number of iterations.  In general, the Time setting results in the fastest performance.  However, due to shifting computational loads on a machine, solution paths may change under the Time setting from one solve to the next, potentially resulting in non-reproducible solutions.  If reproducibility of a runs is a concern, then the Iterations option should be selected.  Under the Solver Decides setting, LINGO chooses the most appropriate strategy.

The Min Seconds field specifies the minimum amount of time to spend on heuristics at each node.

The default settings are 3 for Level, Solver Decides for Cutoff Criterion, and 0 for Min Seconds.