Pepi Stavropoulou

Spoken Dialogue Interfaces: Integrating Usability

Usability is a fundamental requirement for natural language interfaces. Usability evaluation reflects the impact of the interface and the acceptance from the users. This work examines the potential of usability evaluation in terms of issues and methodologies for spoken dialogue interfaces along with the appropriate designer-needs analysis. It unfolds the perspective to the usability integration in the spoken language interface design lifecycle and provides a framework description for creating and testing usable content and applications for conversational interfaces. Main concerns include the problem identification of design issues for usability design and evaluation, the use of customer experience for the design of voice interfaces and dialogue, and the problems that arise from real-life deployment. Moreover it presents a real-life paradigm of a hands-on approach for applying usability methodologies in a spoken dialogue application environment to compare against a DTMF approach. Finally, the scope and interpretation of results from both the designer and the user standpoint of usability evaluation are discussed.

Designing user interfaces for social media driven digital preservation and information retrieval

Social Media provide a vast amount of information identifying stories, events, entities that play the crucial role of shaping the community in an everyday heavy user involvement. This work involves the study of social media information in terms of type (multimodal: text, video, sound, picture) and role players (agents, users, opinion leaders) and the potential of designing accessible, usable interfaces that integrate that information. This case examines the design of a user interface that uses an underlying engine for modality components (plain text, sound, image, video) analysis, social media crawling, contextual search fusion and semantic analysis. The interface is the only point of user interaction to the world of knowledge. This work reports on the usability and accessibility methods and concerns for the user requirements phase and the design control and testing. The findings of the pilot user testing and evaluation provide indications on how the semantic analysis of the social media information can be integrated to the design methodologies for user interfaces resulting in maximization of user experience in terms of social information involvement.

Emotional Prosodic Model Evaluation for Greek Expressive Text-to-Speech Synthesis

In this study we introduce a novel experimental approach towards the evaluation of emotional prosodic models in Expressive Speech Synthesis. It is based on the dimensional emotion expressivity and adopts the Self-Assessment Manikin Test. We applied this experimental approach to evaluate an emotional prosodic model for Greek expressive Text-to-Speech synthesis. We used two pseudo-sentences for each of the Greek and English HMM-based synthetic voices, implemented in the MARY TtS platform. Fifteen native Greek participants were asked to assess eleven emotional states for each sentence. The results show that the “Arousal” dimension is perceived as intended, followed by the “Pleasure” and “Dominance” dimensions’ ratings. These preliminary findings are consistent with the results in previous studies.

Integrating contrast in a framework for predicting prosody

Information Structure (IS) is known to bear a significant effect on Prosody, making the identification of this effect crucial for improving the quality of synthetic speech. Recent theories identify contrast as a central IS element affecting accentuation. This paper presents the results of two experiments aiming to investigate the function of the different levels of contrast within the topic and focus of the utterance, and their effect on the prosody of Greek. Analysis showed that distinguishing between at least two contrast types is important for determining the appropriate accent type, and, therefore, such a distinction should be included in a description of the IS – Prosody interaction. For this description to be useful for practical applications, a framework is required that makes this information accessible to the speech synthesizer. This work reports on such a language-independent framework integration of all identified grammatical and syntactic prerequisites for creating a linguistically enriched input for speech synthesis.

Language Resources and Evaluation for the Support of the Greek Language in the MARY Text-to-Speech

The paper outlines the process of creating a new voice in the MARY Text-to-Speech Platform, evaluating and proposing extensions on the existing tools and methodology. It particularly focuses on the development of the phoneme set, the Grapheme to Phone (GtP) conversion module and the subsequent process for generating a corpus for building the new voice. The work presented in this paper was carried out as part of the process for the support of the Greek Language in the MARY TtS system, however the outlined methodology should be applicable for other languages as well.

User perception knowledge for socially-aware web document accessibility

Social Media provide a vast amount of information identifying stories, events, entities that play the crucial role of shaping the community in an everyday heavy user involvement. This work involves the study of social media information in terms of type (multimodal: text, video, sound, picture) and role players (agents, users, opinion leaders) and the potential of using that information for the design of accessible, usable preservation strategies. The challenge was to analyze the social web and present ways of preserving the web documents with social content in such way as to make them accessible for the future. The web documents should preserve accessible data and stored in such way as to enable intelligent retrieval.

Usability design and testing of an interface for search and retrieval of social web data

The vast amount of data on the web has been extensively harvested for many years for the purpose of digital archiving. In the recent years, however, the social networks contain the sources of most of the debating between the people. Recent approaches include social web information to the archived content for various reasons. This work reports on the usability design and evaluation of a search and retrieval user interface that was designed to retrieve web objects along with semantic information analyzed for the social web. The main task of the interface was to combine the social information with the standard archived content in meaningful and usable ways.

On the Identification and Annotation of Emotional Properties of Verbs

Adequate and reliable lexical resources are essential for effective sentiment analysis and opinion mining. This paper proposes a methodology for the emotional assessment and annotation of words. The process is based on the Self Assessment Manikin test, and is coupled with two psychometric measurements for identifying possible bias due to the annotator’s psychological condition and personality: the EPQ scale and the SCL-90-R scale. A web based tool was developed to support the process. The methodology was validated through a pilot study in which 10 participants were asked to assess the emotional state elicited by each of 75 verbs that were used as stimuli. Results are compared with SentiWordNet’s emotional scoring on respective verbs, and primarily show logical continuity and consistency.