Enriching Affect Analysis Through Emotion and Sarcasm Detection

Affect detection from text is the task of detecting affective states such as sentiment, mood and emotions from natural language text including news comments, product reviews, discussion posts, tweets and so on. Broadly speaking, affect detection includes the related tasks of sentiment analysis, emotion detection and sarcasm detection, amongst others. In this dissertation, we seek to enrich textual affect analysis from two perspectives: emotion and sarcasm. Emotion detection entails classifying the text into fine-grained categories of emotions such as happiness, sadness, surprise, and so on, whereas sarcasm detection seeks to identify the presence or absence of sarcasm in text. The task of emotion detection is particularly challenging due to limited number of resources and as it involves a greater number of categories of emotions in which to undertake classification, with no fixed number or types of emotions. Similarly, the recently proposed task of sarcasm detection is complicated due to the inherent sophisticated nature of sarcasm, where one typically says or writes the opposite of what they mean. This dissertation consists of five contributions. First, we address word-emotion association, a fundamental building block of most, if not all, emotion detection systems. Current approaches to emotion detection rely on a handful of manually annotated resources such as lexicons and datasets for deriving word-emotion association. Instead, we propose novel models for augmenting word-emotion association to support unsupervised learning which does not require labeled training data and can be extended to flexible taxonomies of emotions. Second, we study the problem of affective word representations, where affectively similar words are projected into neighboring regions of an n-dimensional embedding space. While existing techniques usually consider the lexical semantics and syntax of co-occurring words, thus rating emotionally dissimilar words occurring in similar contexts as highly similar, we integrate a rich spectrum of emotions into representation learning in order to cluster emotionally similar words closer, and emotionally dissimilar words farther from each other. The generated emotion-enriched word representations are found to be better at capturing relevant features useful for sentence-level emotion classification and emotion similarity tasks. Third, we investigate the problem of computational sarcasm detection. Generally, sarcasm detection is treated as a linguistic and lexical phenomena with limited emphasis on the emotional aspects of sarcasm. In order to address this gap, we propose novel models of enriching sarcasm detection by incorporating affective knowledge. In particular, document-level features obtained from affective word representations are utilized in designing classification systems. Through extensive evaluation on six datasets from three diverse domains of text, we demonstrate the potential of exploiting automatically induced features without the need for considerable manual feature engineering. Motivated by the importance of affective knowledge in detecting sarcasm, the fourth contribution of this thesis seeks to dig deeper and study the role of transitions and relationships between different emotions in order to discover which emotions serve as more informative and discriminative features for distinguishing sarcastic utterances in text. Lastly, we show the usefulness of our proposed affective models by applying them in a non-affective framework of predicting the helpfulness of online reviews

An exploration of sarcasm detection in children with Attention Deficit Hyperactivity Disorder

This document is the Accepted Manuscript version of the following article: Amanda K. Ludlow, Eleanor Chadwick, Alice Morey, Rebecca Edwards, and Roberto Gutierrez, ‘An exploration of sarcasm detection in children with Attention Deficit Hyperactivity Disorder’, Journal of Communication Disorders, Vol. 70: 25-34, November 2017. Under embargo. Embargo end date: 31 October 2019. The Version of Record is available at doi: https://doi.org/10.1016/j.jcomdis.2017.10.003.The present research explored the ability of children with ADHD to distinguish between sarcasm and sincerity. Twenty-two children with a clinical diagnosis of ADHD were compared with 22 age and verbal IQ matched typically developing children using the Social Inference–Minimal Test from The Awareness of Social Inference Test (TASIT, McDonald, Flanagan, & Rollins, 2002). This test assesses an individual’s ability to interpret naturalistic social interactions containing sincerity, simple sarcasm and paradoxical sarcasm. Children with ADHD demonstrated specific deficits in comprehending paradoxical sarcasm and they performed significantly less accurately than the typically developing children. While there were no significant differences between the children with ADHD and the typically developing children in their ability to comprehend sarcasm based on the speaker’s intentions and beliefs, the children with ADHD were found to be significantly less accurate when basing their decision on the feelings of the speaker, but also on what the speaker had said. Results are discussed in light of difficulties in their understanding of complex cues of social interactions, and non-literal language being symptomatic of children with a clinical diagnosis of ADHD. The importance of pragmatic language skills in their ability to detect social and emotional information is highlighted.Peer reviewe

The Role of Preprocessing for Word Representation Learning in Affective Tasks

Affective tasks, including sentiment analysis, emotion classification, and sarcasm detection have drawn a lot of attention in recent years due to a broad range of useful applications in various domains. The main goal of affect detection tasks is to recognize states such as mood, sentiment, and emotions from textual data (e.g., news articles or product reviews). Despite the importance of utilizing preprocessing steps in different stages (i.e., word representation learning and building a classification model) of affect detection tasks, this topic has not been studied well. To that end, we explore whether applying various preprocessing methods (stemming, lemmatization, stopword removal, punctuation removal and so on) and their combinations in different stages of the affect detection pipeline can improve the model performance. The are many preprocessing approaches that can be utilized in affect detection tasks. However, their influence on the final performance depends on the type of preprocessing and the stages that they are applied. Moreover, the preprocessing impacts vary across different affective tasks. Our analysis provides thorough insights into how preprocessing steps can be applied in building an effect detection pipeline and their respective influence on performance