Underlying Connections Between Algorithms for Nongreedy LDA-L1

Abstract

To solve the essential objective of LDA-L1, NLDA-L1 proposes a nongreedy algorithm by constructing an auxiliary function. In this correspondence, we show that essentially, this algorithm directly solves the objective using a gradient ascending procedure, meaning that the auxiliary function may be not necessary. Then, we further show that NLDA-L1 is a special case of ILDA-L1, which applies the same iterative procedure of ILDA-L1.