I have a problem, which is similar to Assignment Problem, described as follows:
The problem instance has a number of workers and a number of tasks. Any task can only be assigned to a subset of the workers. A task should be assigned to exactly one worker. Each task has a different difficulty, therefore, workers will spend different time to finish each task. It is required to assign tasks as uniformly as possible: all of the workers spent almost the same time to finish assigned tasks.
Translating this problem to an Integer Linear Programming problem and solving it by CoinCbc solver is all I learned from Assignment Problem: the cost function is to minimize the variance of each worker. I searched a lot, assignment problem, balanced assignment problem, constrained assignment problem, quadratic assignment problem, etc. All I found are different from this problem. Although, I can solve the problem now. I want to solve it more efficiently.
Is the problem well studied? Are there any algorithms to solve it more efficiently? (Approximation is acceptable)