Topic Identification
Timothy J. Hazen · 2011
This chapter discusses the problem of identifying the underlying topics beings discussed in spoken audio recordings. It focuses on the issues related to supervised topic classification or detection tasks using labeled training data, but we also discuss approaches for other related tasks including novel topic detection and unsupervised topic clustering. The chapter provides an overview of the common tasks and data sets, evaluation metrics, and algorithms most commonly used in this area of study. From a computational point of view, it may be just as straightforward to create a relevancy ranking system using standard regression techniques as it is to create a binary classification system. The most obvious way to perform speech-based topic ID is to first process the speech data with an automatic speech recognition (ASR) system and then pass the hypothesized transcript from the ASR system directly into standard text-based topic ID system. Controlled Vocabulary Terms speech processing; speech recognition equipment