Author: Valerio Basile

Juan Manuel Pérez will give a talk during his visiting week to the Content-centered Computing group.

In recent years, hate speech has gained great relevance in social networks and other virtual media because of its intensity and its relationship with violent acts against members of protected groups. Due to the incommensurable amount of content generated by users, great effort has been made in the research and development of automatic tools to aid the analysis and moderation of this speech, at least in its most threatening forms.

One of the limitations of current approaches to automatic hate speech detection is the lack of context. Most studies and resources are performed on data without context; that is, isolated messages without any type of conversational context or the topic being discussed. This restricts the available information to define if a post on a social network is hateful or not.

In this talk, I will comment on some experiments we have performed to assess the impact of context in hate speech detection. With this in mind, we built a contextualized dataset for hate speech detection based on user responses to news posts from media outlets on Twitter. This corpus was collected in the Rioplatense dialectal variety of Spanish and focuses on hate speech associated with the COVID-19 pandemic.

For the two proposed tasks using this novel corpus (binary detection; and granular detection, where the system has to predict the attacked characteristics), the classification experiments using state-of-the-art techniques show evidence that adding contextual information improves hate speech detection performance.

When: September 29, 2022, at 11:00

Where: Conference room 3rd floor (Sala Seminari)

Tolúlọpẹ́ Ògúnrẹ̀mí will present her work as a PhD student at Stanford University.

Recognising code-switched speech (alternating between two or more languages or varieties of language across sentences in conversation) is an important technical and social issue essential for modern society. The majority current speech recognisers are trained monolingually and therefore do not perform well on such utterances. The use of Deep Neural Network (DNN) architectures to train models allow for shared representations and provide an opportunity to level them to better handle code-switching. In the two studies contained in this work, we show multilingual fine-tuning of self-supervised speech representations can handle code-switching in a zero-resource scenario and through analysis of the latent representations, that code-switching is encoded in the model. We find that monolingual data is enough for character-level decoding in the code-switched scenario and that representations are not similar to word vectors.

When: 4/7/2022

Where: Sala conferenze on the 3° floor

Antonio Lieto

Inventing novel knowledge to solve problems is a crucial, creative, mechanism employed by humans, to extend their range of action. In this talk, I will show how commonsense reasoning plays a crucial role in this respect. In particular, I will present a cognitively inspired reasoning framework for knowledge invention and creative problem solving exploiting TCL: a probabilistic non-monotonic extension of a Description Logic (DL) of typicality able to combine prototypical (commonsense) descriptions of concepts in a human-like fashion. The proposed approach has been tested in a variety of fields and applications. I will present the obtained results, the lessons learned, and the road ahead of this research path.

See this page https://www.antoniolieto.net/tcl_logic.html for a list of the main papers and applications