PERAN INVESTMENT THINKING DALAM MENCAPAI FINANCIAL GROWTH: STUDI KASUS SAHAM IDXHIDIV20 PERIODE 2025 DENGAN PENDEKATAN MARKOWITZ, SINGLE INDEX MODEL DAN CAPITAL ASSET MARKET LINE (CAPM)

Abstract

This study aims to analyze the information of an optimal portofolio to achieve financial growth using the Markowitz Model, Single Index Model and Capital Asset Pricing Model on stocks included in the IDXHIDIV20 index for the 2025 period. The research method involves calculating returns, risk, and portofolio construction based on each model. The results show that the Markowitz model generates the highest expected return of 63,98% with a risk level of 19,73%. Meanwhile, the Single Index Model produces an expected return of 49,82% with a more selective portofolio composition. The CAPM analysis indicates that not all stocks provide return proportional to their risk, suggesting that market efficiency is not fully achieved. Overall, the findings highlight that the choice of model significantly influences portfolio performance. In addition, investors need to apply rational investment thinking to make better decisions and avoid impulsive behavior such as Fear of Missing Out (FOMO).