<![CDATA[This study examines the influence of advertising and brand ambassadors on consumer purchase decisions in PT Lazada’s Marketplace. The research method used was a quantitative descriptive design with a sample of 57 respondents in Bogor City using purposive sampling. Data were collected through an online questionnaire using the Likert scale technique and analyzed using linear regression, T-test, F-test, and coefficient of determination with SPSS. The study results show that advertising (H1) and brand ambassadors (H2) individually have a positive and significant effect on consumers’' purchasing decisions on Lazada. Regression analysis states that the higher the intensity of advertising and brand ambassadors, the more purchasing decisions are made. The results of the F test (H3) show that advertisements and brand ambassadors together have a significant influence on purchasing decisions. The characteristics of the respondents showed the participation of men and women of various ages. Classical assumption tests, including normality, multicollinearity, and heteroscedasticity tests, showed results that supported the validity of the regression analysis. Determination analysis indicates that 98.3% of the variation in consumer purchasing decisions on Lazada can be explained by advertising and brand ambassadors. This study provides deep insights into the factors that influence consumer purchasing behavior on e-commerce platforms and supports previous findings in the context of the influence of advertising and brand ambassadors on consumer purchasing decisions. The practical implication of this study is that Lazada and similar companies can improve their advertising strategies and choose brand ambassadors wisely to strengthen their positive influence on consumer purchasing decisions. Abstrak Penelitian ini mengkaji pengaruh periklanan dan brand ambassador terhadap keputusan pembelian konsumen di Marketplace PT Lazada. Desain penelitian deskriptif kuantitatif digunakan dengan sampel purposive sebanyak 57 responden di Kota Bogor, Indonesia. Data dikumpulkan melalui kuesioner daring berskala Likert 5 poin dan dianalisis menggunakan regresi linier berganda, uji-t parsial, uji-F simultan, serta koefisien determinasi dengan bantuan SPSS. Hasil penelitian menunjukkan bahwa periklanan (H1) dan brand ambassador (H2) secara individual berpengaruh positif dan signifikan secara statistik terhadap keputusan pembelian konsumen. Koefisien regresi mengindikasikan bahwa semakin tinggi intensitas periklanan dan semakin efektif strategi brand ambassador, maka semakin tinggi pula keputusan pembelian yang dilakukan. Uji F mengonfirmasi bahwa periklanan dan brand ambassador secara bersama-sama memiliki pengaruh signifikan terhadap keputusan pembelian (H3). Uji asumsi klasik (normalitas, multikolinearitas, dan heteroskedastisitas) mendukung validitas model regresi. Koefisien determinasi (R² = 0,983) menunjukkan bahwa 98,3% variasi keputusan pembelian konsumen dapat dijelaskan oleh kedua prediktor. Studi ini memberikan bukti empiris terkini mengenai efektivitas alat promosi digital di salah satu platform e-commerce terbesar di Asia Tenggara serta implikasi praktis bagi pengelola marketplace dalam mengoptimalkan strategi periklanan dan pemilihan brand ambassador. Keterbatasan penelitian mencakup desain potong lintang, fokus geografis tunggal, dan potensi common method bias pada data survei self-report. Kata Kunci: periklanan, brand ambassador, keputusan pembelian, Lazada, e-commerce, regresi linier berganda, Indonesia.]]>
