Category: portfolio theory

  • Efficient frontier calculator

    Efficient frontier calculator

    In modern portfolio theory, the efficient frontier represents the collection of all efficient portfolios within a market. Efficient portfolios offer the best risk-return tradeoff and, as such, are superior to inefficient portfolios, which are suboptimal. In this lesson, we explain how investors can trace the efficient frontier using mean-variance optimization (the topic of the previous […]

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  • Mean-variance optimization

    Mean-variance optimization

    According to modern portfolio theory, investors are concerned about the “mean” and “variance” of asset returns, where the former captures the “centrality” and the latter the “spread” (or “riskiness”) of potential returns. As such, investors engage in mean-variance optimization. That is, they seek the portfolios that offer the best tradeoff between risk and return. In […]

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  • Idiosyncratic risk

    Idiosyncratic risk

    What is idiosyncratic risk? It is the type of risk that affects either a single security such as a stock or a small group of securities. This is in contrast to systematic risk, which affects all risky securities in a particular market. The word “idiosyncratic” does not commonly feature in daily language. Many people may […]

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  • What is the market portfolio?

    What is the market portfolio?

    The market portfolio is the market value-weighted portfolio of all risky assets in an economy. In this post, we show how the market portfolio is equivalent to the optimal risky portfolio when all investors behave according to the modern portfolio theory. Learning objectives Moving from the optimal risky portfolio to the market portfolio According to […]

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  • What is the optimal risky portfolio?

    What is the optimal risky portfolio?

    In the previous post, we explained that when there is no risk-free asset in an economy, investors should invest in one of the efficient portfolios that lie on the efficient frontier based on their risk tolerance. We added that, if a risk-free asset exists, then there is a unique efficient portfolio that all investors should […]

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