Technical debt reduction using epsilon-Nash equilibrium for the perturbed software refactor game model

Abstract

Technical debt (TD) is a metaphor that is one of the reasons for software to become obsolete. The process of refactoring can be effectively applied to reduce the technical debt and the improvement of other vital quality attributes such as abstraction, inheritance and coupling. This paper discusses a refactoring model that can be applied for an object oriented software system for improved quality by applying the concepts of game theory. A multi-player perturbed software refactor game model is developed, that models inheritance, abstraction, coupling and the technical debt, as multiple players of the game. An optimal strategy for refactoring the source code is arrived by calculating the ε-Nash equilibrium of the perturbed game. The results attained are compared against the popular genetic algorithm (GA), artificial bee colony (ABC) and simulated annealing (SA) optimisation algorithms, taking three open source Java project samples.