Initial Return is the product of a collaboration between finance professionals, academics, and investors. We produce high-quality, educational content for investors, traders, and finance students.
We have so far learned how to calculate the risk and return of portfolios and how to trace an efficient frontier through mean-variance optimization. It is now time to introduce a special portfolio that will play a significant role when we discuss the CAPM: The market portfolio. What is the market portfolio? The market portfolio is the […]
The capital asset pricing model (or CAPM) is among the most widely-used asset pricing models by stock analysts and portfolio managers. Its popularity arises from its simplicity and elegance. Analysts can use it to forecast returns or to estimate the cost of equity. In this post, we offer a CAPM calculator and discuss the model […]
In a market with multiple risky assets, the minimum variance portfolio is a particular combination of those assets that yields the minimum volatility. To be more specific, consider the market depicted in Figure 1. Here, the blue curve represents the efficient frontier. That is, all portfolios that lie on it are efficient portfolios (e.g., D […]
Treynor ratio is a popular risk-adjusted performance measure. It was developed by the American economist Jack Treynor in the mid-1960s (you can find the reference for his seminal paper at the bottom of this page). It is a measure of how much “excess return” (i.e., return above the risk-free rate) a security (stock, bond, mutual fund, […]
Sharpe ratio is among the most widely used performance evaluation metrics in the fund management industry. It is a reward-to-risk ratio, such that it captures the (excess) return an asset (e.g., stock) generates per unit of (total) risk, which is measured by return volatility. It was developed by Nobel laureate William F. Sharpe, who is […]
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 […]
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 […]
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 […]
Different stocks offer different levels of expected return. What causes stock A’s expected return to be higher than stock B’s expected return? How does the expected return on a risky asset relate to the risk-free rate of return? In this post, we answer both questions by introducing the concept of risk premium. Jump to: Risk […]
We, humans, have a general tendency to avoid taking risks when we can, a notion that we refer to as risk aversion. This has the important implication that when we are faced with a choice between a safe payoff and a risky one, we’d opt for the latter only if it entails a sufficient risk […]
Step-by-step tutorials:
Downloading stock price data
Plotting stock prices and returns
Creating a histogram of stock returns
Descriptive statistics for stock returns
Computing the correlation between two stocks
Modern portfolio theory:
Portfolio return
Portfolio risk
Efficient frontier
Optimal risky portfolio
Market equilibrium:
Capital asset pricing model (CAPM)
Arbitrage pricing theory (APT)