Discriminative Learning of Two-Dimensional Probabilistic Context-Free Grammars for Mathematical Expression Recognition and Retrieval

Ernesto Noya, José-Miguel Benedí, Joan-Andreu Sánchez, Dan Anitei

Abstract: We present a discriminative learning algorithm for the estimation of two-dimensional Probabilistic Context-Free Grammars in the context of Mathematical Expressions Recognition and Retrieval. This algorithm is based on a generalization of the H-criterion, as the objective function, and the growth transformations as the optimization method. In addition, experimental results are reported on the Im2Latex-100k dataset, studying the performance of the estimated models depending on the length of the mathematical expressions and the number of admissible errors in the metric used.