Sentiment Analysis

Measures of bias in news and social media coverage are essential when investigating trends and differing perceptions of various interest groups. webLyzard uses sentiment information to (i) classify and sort search results, (ii) enrich visualizations such as tag cloudsgeographic maps and information landscapes, and (iii) provide data services for accurately tagging third-party content.

Economic Relevance. A significant portion of news and social media coverage contains opinions with clear economic relevance – product and travel reviews, for example, or the articles of well-known and respected bloggers who influence consumer purchase decisions. Analyzing and acting upon user-generated content is becoming imperative for decision makers who aim to engage with large user communities.

Extracting Opinions from Multilingual Resources. The user-generated content gathered from various social media platforms is noisy, unstructured, and multilingual. Processing this type of content requires robust text mining techniques, ranging from simple spelling corrections to more complex tasks such as sentiment analysis or the identification of named entities (locations, persons, organizations). Multilingual capabilities are becoming increasingly important when applying these techniques to global networks. This goes beyond merely detecting the language(s) used, a comparably straightforward task. It requires specific language resources (sentiment lexicons), and a system that is capable of processing grammatical structures and consider the idiosyncrasies of specific language communities.

Context-Awareness and Dealing with Ambiguity. The ever increasing amount of articles and the limits of human cognition require automated approaches to analyzing the sentiment expressed in online content. As part of opinion mining, sentiment analysis identifies and aggregates polar opinions – i.e., positive or negative statements about facts. For achieving accurate results, one needs to deal with the inherent ambiguities of the human language. webLyzard’s method of automatically determining has been continuously optimized since 2003, giving particular attention to the context of opinionated terms when resolving such ambiguities.

New Journal Articles. Recent articles published in Knowledge-Based Systems and IEEE Intelligent Systems, two prestigious scientific journals, present webLyzard’s novel approach to contextualization. These articles describe how the underlying methods were developed, point out their advantages over existing approaches, and include detailed evaluation sections based on user-generated online reviews of movies (IMDb), hotels (TripAdvisor), and products (Amazon).

While the first IEEE article (2013) focuses on disambiguation and the generation of contextualized sentiment lexicons, the Knowledge-Based Systems article extends the presented methods in order to enrich semantic knowledge bases and integrate external affective resources into the opinion mining process. The second IEEE article (2017) outlines how to increase the granularity of the approach by focusing on aspects to which emotional values apply, for example product features (e.g., a digital camera’s resolution), or perceptions of a specific event (e.g., as part of a sponsorship agreement).

Other Selected Publications