Graphical and multi-modal data stream query language Sample Clauses

Graphical and multi-modal data stream query language. Success criteria, measures and metrics to be evaluated in order to assess the overall usability (i.e., the extent to which the visual and multi-modal environment can be used by identified users to achieve specified goals with effectiveness, efficiency and satisfaction one or more contexts of use) include:  Effectiveness: accuracy and completeness with which users achieve specified goals; it can be measured in terms of: – percentage of goals achieved (e.g., number of queries successfully built/intended number of queries); – percentage of tasks completed successfully on first attempt (e.g., number of queries successfully built on first attempt); – percentage of users successfully completing a given task (e.g., define a set of queries); – average accuracy of completed tasks (e.g., evaluating produced queries wrt intended queries); – percentage of errors performed by users or reported by the system (e.g., mean number of mistakes/problems for building a visual query); – mean number of assistance operations required per task  Efficiency: resources expended in relation to the accuracy and completeness with which users achieve goals; it can be measured in terms of: – time to complete a task (e.g., mean time to build a visual query); – tasks completed per time unit (e.g., number of queries built per time unit); – relative time spent by users compared with time spent by an expert user to perform a task (e.g., to build a query);  Satisfaction: freedom from discomfort, and positive attitudes towards the use of the visual and multi-modal environment; it can be measured through questionnaires, including: – rating scale for satisfaction of provided features and interaction modalities – rating scale for ease of use and comprehensibility of the environment – rating scale for ease of learning (learnability) – rating scale for provided support facilities – rating scale for attractiveness of the graphical environment Additional metrics to be evaluated, mainly related to the multi-modal interaction environment, include:  Responsiveness: ability of the environment to perform (near)real-time interaction modalities recognition  User adaptability and feedback: ability of the environment to adapt the interaction modality to users' needs and requirements, as well as to provide feedback about the correctness of the provided input (voice, gestures, etc.)  Learnability: learning rate and ability of the user to perform and remember available actions provided by the environment, to...