This article presents a theoretical review of and methodological guidelines for the study of two key notions in second language acquisition research, complexity and difficulty. The term "complexity" has gained considerable currency over the past decades and has taken on a wide range of meanings. We argue for a more restricted…

Second language (L2) viewing with captions (i.e., L2 on-screen text) is now a proliferating as well as promising area of L2 acquisition research. The goal of the present meta-analysis was to examine (a) the relationship between captioned viewing and incidental vocabulary learning and (b) what variables related to learners, treatment, methodology,…

Researchers often make claims regarding the importance of predictor variables in multiple regression analysis by comparing standardized regression coefficients (standardized beta coefficients). This practice has been criticized as a misuse of multiple regression analysis. As a remedy, I highlight the use of dominance analysis and random forests, a…

Second language acquisition (SLA) research offers valuable insight on how languages are learned and how they coexist and influence each other. Sign language learners offer unique perspectives on SLA, allowing researchers to test theories that are otherwise constrained by access to only one modality. Current literature on sign language learning…

This paper introduces the Lang-Track-App, a smartphone application and backend system to aid second language acquisition researchers in implementing the experience sampling method (ESM). Surveying research participants with the Lang-Track-App multiple times per day can yield exceptionally rich data that can be analyzed in multiple ways. This…

Self-determination theory has been applied in various educational contexts. Language learning researchers have used factor analysis and structural equation modeling to investigate measures designed for this theory, but Rasch analysis has not been conducted. The Basic Psychological Needs Satisfaction and Frustration Scale (BPNSFS) and the Language…