Potential clusters The wilayas within the cluster 1 Adrar,Laghouat,Batna,Tebessa,Tlemcen,Tiaret,Djelfa,Sétif,Saida,Sidibelabbes,Annaba,GhardaiaMascara, Ouargla, ElTarf, Tindouf, Tissemsilt, Khenchela, SoukAhras,AinDefla, Ghardaia 2 OumElBouaghi,Biskra,Bechar,Tamanrasset,Jijel,Skikda,Guelma,Constantine,Mostaganem, Oran, ElBayadh,ElOued,Mila,Naama,AinTémouchent,Relizane 3 Chlef,  Béjaia,  Blida,  Bouira,  Tizi-Ouzou, Alger,  Médéa,  M’Sila,  Illizi, Bordj-Bou- Arrérij, Boumerdes, Tipaza

Source: realized by authors.

Table 2: Potential clusters by the two-step cluster method.