Brand Image and Promotion: Experimental Studies on Willingness to Buy in Stocks Context

Abstract

Retail investing in Indonesia is growing despite the sharp 2026 decline of the Indonesia Composite Index (IHSG), yet how marketing stimuli shape investment behavior remains unclear. This study investigates the effects of brand image and promotion on willingness to buy (WTB) and purchase decision in the context of stock investment. Using a randomized between-subjects experimental design with three conditions—Brand Image, Promotion, and Control—this study enrolled 331 adult participants with basic knowledge of equity investment. WTB was measured before and after stimulus exposure using a six-item Likert scale, while purchase decision was captured via a simulated binary buy/skip task. ANCOVA results revealed that neither brand image nor promotion produced a statistically significant effect on post-test WTB when controlling for pre-test scores (F = 2.583, p = .109), whereas the pre-test score itself was a strong predictor (F = 394.672, p < .001, R² = .623). However, chi-square analysis demonstrated a significant difference in actual purchase decisions across conditions (χ² = 12.260, df = 2, p = .002), with the brand image group exhibiting a higher proportion of buy decisions than the promotion group. These findings highlight an intention–behavior gap in stock investment contexts, suggesting that brand image operates through affective and trust-based pathways to influence actual behavior, even when explicit purchase intentions remain stable. The results underscore the importance of measuring behavioral outcomes alongside intentional indicators in marketing and behavioral finance research.

Investasi ritel di Indonesia terus tumbuh meskipun IHSG merosot tajam pada 2026, namun pengaruh stimulus pemasaran terhadap perilaku investasi masih belum jelas. Penelitian ini menginvestigasi pengaruh brand image dan promosi terhadap willingness to buy (WTB) dan keputusan pembelian dalam konteks investasi saham. Menggunakan desain eksperimen antara-subjek teracak dengan tiga kondisi—Brand Image, Promosi, dan Kontrol—penelitian ini melibatkan 331 partisipan dewasa yang memiliki pengetahuan dasar mengenai investasi saham. WTB diukur sebelum dan sesudah paparan stimulus menggunakan skala Likert enam item, sementara keputusan pembelian direkam melalui tugas simulasi biner beli/lewati. Hasil ANCOVA menunjukkan bahwa brand image maupun promosi tidak menghasilkan efek yang signifikan secara statistik terhadap skor WTB post-test setelah dikontrol oleh pre-test (F = 2,583, p = ,109), sedangkan skor pre-test sendiri merupakan prediktor yang kuat (F = 394,672, p < ,001, R² = ,623). Namun, analisis chi-square menunjukkan perbedaan yang signifikan dalam keputusan pembelian aktual antar kondisi (χ² = 12,260, df = 2, p = ,002), dengan kelompok brand image menunjukkan proporsi keputusan membeli yang lebih tinggi dibandingkan kelompok promosi. Temuan ini menyoroti fenomena intention–behavior gap dalam konteks investasi saham, menunjukkan bahwa brand image bekerja melalui jalur afektif dan berbasis kepercayaan untuk memengaruhi perilaku aktual, bahkan ketika niat beli eksplisit tetap stabil.