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@article{190919,
        author = {Anand B Nair and Aphedh Mohan and Suraj P Shenoy and Athul Antony Rajeev and Pooja Prakash and Dr. R.Suma},
        title = {PORTFOLIO THEORY AND MANAGEMENT: MARKOWITZ MODEL, EFFICIENT MARKET HYPOTHESIS, AND ARBITRAGE PRICING THEORY},
        journal = {International Journal of Innovative Research in Technology},
        year = {2026},
        volume = {12},
        number = {8},
        pages = {4287-4289},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=190919},
        abstract = {Portfolio theory and management play a crucial role in modern finance by helping investors make rational investment decisions under conditions of risk and uncertainty. The primary objective of portfolio management is to maximize expected returns while minimizing risk through diversification. This paper discusses three foundational theories of portfolio management: the Markowitz Mean–Variance Model, the Efficient Market Hypothesis (EMH), and the Arbitrage Pricing Theory (APT). The Markowitz model emphasizes diversification and the efficient frontier to optimize risk–return trade-offs. The Efficient Market Hypothesis explains how information is reflected in asset prices and highlights the limitations of consistently outperforming the market. The Arbitrage Pricing Theory extends asset pricing by incorporating multiple systematic risk factors influencing returns. The study also highlights practical applications of these theories in modern financial markets and discusses their limitations. The paper provides a structured understanding of portfolio theory relevant for students, academicians, and practitioners.},
        keywords = {Portfolio Management, Markowitz Model, Efficient Market Hypothesis, Arbitrage Pricing Theory, Risk and Return, Asset Allocation},
        month = {January},
        }