To address the data sparsity problem in short text understanding, various alternative topic models leveraging word embeddings as background knowledge have been developed recently. However, existing models combine auxiliary information and topic modeling in a straightforward way without considering human reading habits. In contrast, extensive studies have proven that it is full of potential in textual analysis by taking into account human attention. Therefore, we propose a novel model, Attentional Segmentation based Topic Model (ASTM), to integrate both word embeddings as supplementary information and an attention mechanism that segments short text documents into fragments of adjacent words receiving similar attention. Each segment is assigned to a topic and each document can have multiple topics. We evaluate the performance of our model on three real-world short text datasets. The experimental results demonstrate that our model outperforms the state-of-the-art in terms of both topic coherence and text classification.

One of the prevalent studies on Topic Detection and Tracking (TDT) is topic evolution. With the emergence of Internet data, there is a clear need for intuitive and adaptive methods to analyze a series of evolutions. Most approaches completely depend on topic models and only focus on whether topics are changed while ignoring the degree of changes, resulting in poor quality topics and insensitivity of changes. In this paper, we propose a framework of topic evolution based on semantic connections which not only indicates the content similarity between documents but also shows the time decay for an adaptive number of topics and rapid responses to the changes of contents. Additionally, semantic connection features can be used to visualize topic evolution, which makes the analyses much easier. For empirical studies, three data sets in real applications are chosen to prove the effectiveness of our method, and the results show that our method has a better performance in reducing redundant topics, avoiding topic suppression, and discerning the vanishment of old topics and the appearance of new topics.

Contrary to previous studies on topic evolution that directly extract topics by topic modeling and preset the number of topics, we propose a method of topic evolution based on semantic connection for an adaptive number of topics and rapid responses to the changes of contents. Semantic connection not only indicates the content similarity between documents but also shows the time decay, so semantic connection features can be used to visualize topic evolution, which makes the analyses of changes much easier. Preliminary experimental results demonstrate that our method performs well compared to a state-of-the-art baseline on both qualities of topics and the sensitivity of changes.