abstract: Social media is a medium that contains rich information which has been shared by many users every second every day. This information can be utilized for various outcomes such as understanding user behaviors, learning the effect of social media on a community, and developing a decision-making system based on the information available. With the growing popularity of social networking sites, people can freely express their opinions and feelings which results in a tremendous amount of user-generated data. The rich amount of social media data has opened the path for researchers to study and understand the users’ behaviors and mental health conditions. Several studies have shown that social media provides a means to capture an individual state of mind. Given the social media data and related work in this field, this work studies the scope of users’ discussion among online mental health communities. In the first part of this dissertation, this work focuses on the role of social media on mental health among sexual abuse community. It employs natural language processing techniques to extract topics of responses, examine how diverse these topics are to answer research questions such as whether responses are limited to emotional support; if not, what other topics are; what the diversity of topics manifests; how online response differs from traditional response found in a physical world. To answer these questions, this work extracts Reddit posts on rape to understand the nature of user responses for this stigmatized topic. In the second part of this dissertation, this work expands to a broader range of online communities. In particular, it investigates the potential roles of social media on mental health among five major communities, i.e., trauma and abuse community, psychosis and anxiety community, compulsive disorders community, coping and therapy community, and mood disorders community. This work studies how people interact with each other in each of these communities and what these online forums provide a resource to users who seek help. To understand users’ behaviors, this work extracts Reddit posts on 52 related subcommunities and analyzes the linguistic behavior of each community. Experiments in this dissertation show that Reddit is a good medium for users with mental health issues to find related helpful resources. Another interesting observation is an interesting topic cluster from users’ posts which shows that discussion and communication among users help individuals to find proper resources for their problem. Moreover, results show that the anonymity of users in Reddit allows them to have discussions about different topics beyond social support such as financial and religious support. / Dissertation/Thesis / Doctoral Dissertation Computer Science 2019

Through this study, we discussed cases of hypercorrection present in the speech of unemployed adults in the city of Maceió. With this purpose in mind, we based our focus on the theoretical premises of the Variationist Sociolinguistic Theory. (LABOV,2008 [1972]). Our main goal was to demonstrate that the occasions of hypercorrection in the speech of these informants are motivated by linguistic and extra-linguistic factors, being, the last referred, relative to sex and age. The corpus was collected by means of interviews with 24 (twenty four) adult speakers of both sexes, belonging to two groups of age: the first group, involving people of ages 17 through 30; the second, informants of ages 31 through 55, in the Sine - Sistema Nacional de Emprego, of the state of Alagoas. As a result of this study, we have concluded that the hypercorrections may occur on the fields of phonetics, morphology, semantics and syntax, being susceptible to influence from the following extra-linguistic factors: age, sex and situational context. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Neste trabalho, fizemos uma discussão sobre os casos de hipercorreção presentes na fala de adultos desempregados da cidade de Maceió. Com este intuito, nos baseamos nos pressupostos teóricos da Teoria da Variação (LABOV, 2008 [1972]). Tivemos como objetivo principal demonstrar que os casos de hipercorreção presentes na fala desses informantes são motivados por fatores linguísticos e extralinguísticos, tais como: o sexo e a idade. O corpus utilizado foi coletado por meio entrevistas com 24 falantes adultos de ambos os sexos pertencentes a dois grupos de idade: o primeiro envolvendo pessoas de 17 a 30 anos; o segundo, informantes de 31 a 55 anos, no Sine - Sistema Nacional de Emprego, do estado de Alagoas. Como resultado desse estudo, obtivemos que as hipercorreções podem ocorrer no campo da fonética, morfologia, semântica e sintaxe, podendo ser influenciadas pelos seguintes fatores extralinguísticos: idade, sexo e contexto situacional.