research synthesis

Dialogue systems for language learning: a meta-analysis

A meta-analysis of effectiveness studies on dialogue-based CALL, based on 17 studies and $k = 100$ individual effect sizes. We use Morris and DeShon's (2002) formulas to compute comparable effect sizes across designs, and analyse them through a multilevel random-effects model. Results confirm that dialogue-based CALL practice has a significant medium effect size on L2 proficiency development ($d = 0.59$). Extensive moderator analyses on several learning outcomes of different types and features of dialogue-based CALL (type of interaction, modality, agent embodiment, etc.) confirm the effectiveness of form-focused and goal-oriented systems, system-guided interactions, corrective feedback provision, and gamification features. Significant effects for lower proficiency learners, and on vocabulary, morphosyntax, holistic proficiency and accuracy are established.

Discussing with a computer to practice a foreign language: research synthesis and conceptual framework of dialogue-based CALL

This article presents the results of a systematic review of the literature on dialogue-based CALL. Applications allowing a learner to have a conversation in a foreign language with a computer have been studied under different traditions (*intelligent tutoring systems*, *dialogue systems*, *conversational agents*, *chatbots*...). We attempt to offer a structured overview of these efforts into a conceptual framework, including an **operational definition** of dialogue-based CALL and a **typology of systems** (4 types: narrative, form-focused, goal-oriented and reactive systems) and types of dialogue, with their corresponding interactional, instructional and technological traits. We summarize the main results from empirical studies on such systems, and discuss the impact of dialogue-based CALL on motivation and L2 development.

Instructional design and natural language processing in dialogue-based CALL

Dialogue-based computer-assisted language learning (CALL) encompasses applications that allow a learner to practice a foreign language by carrying a conversation with a computer through unconstrained input. Such systems, whether speech or text-based, …

Dialogue-based CALL: an overview of existing research

We propose a common definition for dialogue-based CALL and establish a first overview of the literature in the domain, from a systematic literature review of 138 papers. Results show a scattered research field, with 4 main disciplinary approaches, each preferring a certain keyword for referring to the domain.

Conversational agents for language learning: state of the art and avenues for research on task-based agents

Conversational agents are seen as a way to offer an anxiety-free L2 practice environment for learners, in the hope that it would produce similar proficiency improvements as those obtained in a chat with a human interlocutor. Various approaches have …