Heuristics can be categorized broadly into three different categories: construction heuristics, im-
provement heuristics and metaheuristics. These three categories are explained in the next three
sections (Section 3.2.1 to 3.2.4).
Laporte and Semet [2002] proposed a different classification of heuristics for vehicle routing
problems. The propose two main classes classical heuristics and metaheuristics. The class of
classical heuristics is divided into three groups: constructive heuristics, two-phase heuristics and
improvement methods. The term two-phase heuristics covers heuristics that divide the construction
into two phases: a clustering phase and a routing phase. In the classification of heuristics used in
this thesis, two-phase heuristics are seen as construction heuristics.