“…A combination of VAT and topic models are used in our proposed framework (hence, they called as VNMF, VLDA, VLSI, and VPLSI) and experimented with Euclidean, cosine based and multiviewpoint cosine based metrics. Evaluation of proposed techniques are measured with five external validity indexes, namely, clustering accuracy (CA) [41], normalized mutual information (NMI) [42], precision (P), recall (R) and F-Score (F) [43], [44] and seven internal validity indexes viz., Davies-Bouldin index (DB) [55], [56], [60], Calinski-Harabasz Index (CHI) [55], [56], Silhouette Index (SI) [55], [56], Xie-Beni Index (XI) [57], Partition Coefficient (PC) [59], Partition Entropy Index (PEI) [57], [58], and Separation Measure (SM) [60]. Health tweets are assigned to topic clusters which are maintained the highest similarity with the topic clusters to improve the value of CA.…”