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In this paper, for a given sequentially Yoneda-complete T_1 quasi-metric space (X,d), the domain theoretic models of the hyperspace K_0(X) of nonempty compact subsets of (X,d) are studied. To this end, the ω-Plotkin domain of the space of formal balls BX, denoted by CBX is considered. This domain is given as the chain completion of the set of all finite subsets of BX with respect to the Egli-Milner relation. Further, a map ϕ:K0(X)→CBX is established and proved that it is an embedding whenever K_0(X) is equipped with the Vietoris topology and respectively CBX with the Scott topology. Moreover, if any compact subset of (X,d) is d^{-1}-precompact, \phi is an embedding with respect to the topology of Hausdorff quasi-metric H_d on K_0(X). Therefore, it is concluded that (CBX,\sqsubseteq,\phi) is an ω-computational model for the hyperspace K_0(X) endowed with the Vietoris and respectively the Hausdorff topology. Next, an algebraic sequentially Yoneda-complete quasi-metric D on CBXisintroducedinsuchawaythatthespecializationorder\sqsubseteq_DisequivalenttotheusualpartialorderofCBXand,furthermore,\phi:({\cal K}_0(X),H_d)\rightarrow({\bf C}{\bf B}X,D)isanisometry.Thisshowsthat(CBX,⊑,ϕ,D)isaquantitative\omega$-computational model for (K_(X),H_d).