Tracing Causal Relationships in L2 Learning via Granger Causality

Area of Science:

• Psycholinguistics
• Second Language Acquisition Research
• Quantitative Linguistics

Background:

• Longitudinal second language acquisition (SLA) research faces challenges in understanding dynamic causal relationships between learner variables and linguistic development.
• Existing methods struggle to establish the directionality of influence among interacting factors over time.

Purpose of the Study:

• To introduce and illustrate Granger Causality as a statistical method for analyzing longitudinal SLA data.
• To explore causal relationships between L2 development measures (C-Test, speech fluency) and individual differences (operation span, motivation, wellbeing) in later-life learners.

Main Methods:

• Explanation of the Granger Causality concept and its application.
• Longitudinal data analysis using weekly measures of L2 performance and individual difference variables.
• Statistical examination of asymmetric causal patterns.

Main Results:

• Granger Causality identified several asymmetric causal relationships among the studied variables.
• The analysis demonstrated distinct directions of influence between learner factors and language development over time.

Conclusions:

• Granger Causality is a valuable tool for determining the directionality of relationships in longitudinal SLA studies.
• The findings contribute to understanding the complex interplay of factors in later-life language learning.