Based on the motivation theories, we postulated that interest in learning languages influences the self-efficacy beliefs of students about their capabilities as second/foreign language (L2) English learners. This study examined the longitudinal causal relation between affective interest and cognitive self-efficacy in the L2 motivational context using the Gyeonggi Education Panel Study (GEPS) data from South Korea. A secondary school student sample from 2015–2020 GEPS over six years comprised 6,314 students (3,189 males and 3,125 females). Using a parallel growth model (PPM) with Mplus 8.4, the results indicated that the initial level and growth rate of L2 English interest positively predicted L2 English self-efficacy. Subsequently, the initial level of L2 English interest exhibited a negative cross-effect on the growth rate of L2 English self-efficacy. Finally, the sequential causal effect of L2 English interest on self-efficacy was found across the six-year period. The findings are discussed in terms of the pedagogical implications in English learning and teaching practices and further research.

1. INTRODUCTION
2. LITERATURE REVIEW
    2.1. Interest and Self-efficacy in Motivational Framework
    2.2. Causality Between Interest and Self-efficacy in L2 Motivation Domain
    2.3. Effect of L2 English Self-efficacy on English Achievement
3. METHODOLOGY
    3.1. Sample
    3.2. Measure
    3.3. Data Analysis
    3.4. Missing Values
4. RESULTS
    4.1. Descriptives
    4.2. LGCM and PPM Model Building
    4.3. The Dynamic Relation between L2 English Interest and Self-efficacyModeling
    4.4. Modelling Sequentially the Contingent Process Over Time
    4.5. Effect of Self-efficacy Trajectories on English Achievement Over Time
5. Discussion
6. Conclusion
REFERENCES

• Youngkyo Oh(Lecturer, Department of Education, Chonnam National University, Youngbong-ro 77, Bukgu, Gwangju 61186, Korea)