Abstract

This study examines how subjective norms and perceived behavioral control influence consumers’ online purchase intentions by integrating the Theory of Planned Behavior and Theory of Reasoned Action frameworks. The purpose was to analyze the relative strength of these psychosocial factors in predicting e-commerce behavior across different product categories. Data was collected through a mixed-methods approach involving an online survey of 379 participants. Measurement instruments demonstrated strong reliability (Cronbach’s α ranging from 0.82 to 0.91). PLS-SEM analysis confirmed the model’s validity with satisfactory convergent (AVE>0.5) and discriminant validity measures (HTMT<0.85). Structural equation modeling revealed that perceived behavioral control had a stronger direct effect (β=0.42, p<0.001) on purchase intention than subjective norms (β=0.28, p<0.01). Particularly notable was the amplified influence of subjective norms for publicly consumed goods and among younger demographics. The findings contribute to e-commerce theory by demonstrating the context-dependent nature of these behavioral predictors and provide practical implications for online retailers. The research contributes by quantifying the differential impact of subjective norms and perceived behavioral control on online purchase intentions across various online shopping platforms. It identifies contextual moderators of these relationships and offers validated measurement tools that integrate both Theory of Planned Behavior and Theory of Reasoned Action frameworks for more nuanced e-commerce behavior prediction.