What Does Alpha Mean in Investing and What Are Its Key Considerations?

Dec 26, 2023 By Susan Kelly

Alpha, represented by the Greek letter α, is a key concept in investment that measures an investment strategy's effectiveness in outperforming the market. It's essentially the additional gain beyond what's expected based on market movements, adjusted for risk. Alpha is often mentioned alongside beta (β), another Greek letter used in finance to denote the overall volatility or risk of the market, also known as systematic market risk.

In the world of finance, alpha is a pivotal performance metric. It highlights whether a strategy, trader, or portfolio manager has succeeded in surpassing the market return or other established benchmarks over a certain timeframe. Viewed as the active return on investment, alpha evaluates an investment’s performance against a market index or benchmark that symbolizes the market's overall movement.

Alpha is a primary goal for active portfolio managers, particularly in diversified portfolios. Diversification aims to mitigate unsystematic risk. Since alpha represents how a portfolio’s returns measure up against a benchmark, it's often seen as a reflection of the value a portfolio manager contributes to or detracts from a fund’s performance.

In simpler terms, alpha is the return on an investment, not just a byproduct of broad market trends. An alpha of zero implies that the portfolio or fund is perfectly aligned with the benchmark index, suggesting that the manager hasn't added or lost value compared to the overall market.

Utilizing Alpha in Investment Strategies

The concept of alpha revolves around the idea of excess return. It's the difference between an investment’s return and the return of a benchmark index. Alpha can be either positive, demonstrating superior performance, or negative, indicating underperformance. This measure is tied to the skill of active investing, as opposed to beta, which can be achieved through passive index investing.

Alpha is one of the five key technical risk ratios in investment, along with beta, standard deviation, R-squared, and the Sharpe ratio. These ratios, central to modern portfolio theory (MPT), are statistical tools designed to help investors understand the risk-return dynamics of an investment.

The relevance of alpha investing reviews strategies gained traction with the introduction of smart beta index funds. These funds, linked to benchmarks like the Standard & Poor's 500 index and the Wilshire 5000 Total Market Index, strive to boost portfolio performance by focusing on specific market segments.

Despite the allure of alpha in portfolios, most index benchmarks often outperform asset managers. This has led to investor preference shifting towards low-cost, passive online advisors, commonly known as robo-advisors. These platforms predominantly invest in index-tracking funds, adhering to the philosophy that if beating the market is challenging, it's better to align with it.

This trend is also fueled by the fees charged by traditional financial alpha investment advisors. For instance, if an advisor achieves an alpha of zero but charges a fee, it results in a net loss for the investor. Consider a scenario where Jim, a financial advisor, sets 1% for managing a portfolio and produces an alpha of 0.75 over a year for his client, Frank. While Jim improves Frank’s portfolio performance, the fee exceeds the generated alpha, leading to an overall loss for Frank. This underscores the importance of weighing advisory fees against performance and alpha.

Efficient Market Hypothesis and Its Implications

The Efficient Market Hypothesis (EMH) argues that market prices always reflect all available information, implying that securities are accurately priced and markets are efficient. According to EMH, it’s not feasible to consistently identify and exploit market mispricings, as they are either non-existent or corrected quickly.

Historical data comparing the performance of active mutual funds against their passive benchmarks shows that less than 10% of active funds maintain a positive alpha over a decade or more. This figure drops further when taxes and fees are factored in, indicating the rarity of sustainable alpha.

The concept of beta risk, which can be managed through diversification and hedging, leads some to question the existence of alpha. They argue that alpha is a reward for unhedged risks that have either been missed or ignored.


Alpha's significance in investment strategies can be better understood through two real-world instances involving a fixed-income ETF and an equity ETF:

Consider the iShares Convertible Bond ETF (ICVT), a lower-risk fixed-income investment. This ETF follows a specialized index, the Bloomberg U.S. Convertible Cash Pay Bond >'' $250MM Index. On February 28, 2022, it had a 3-year standard deviation of 18.94% and a year-to-date return of -6.67%. During the same period, its benchmark index returned -13.17% (negative alpha investing). Hence, ICVT's alpha stood at 6.5%, compared to the Bloomberg U.S. Aggregate Index, which has a similar standard deviation. However, the alpha might be misleading as convertible bonds, which ICVT comprises, carry higher risk profiles than legal bonds, and the aggregate bond index might not be the most fitting benchmark.

Another example is the WisdomTree U.S. Quality Dividend Growth Fund (DGRW), an equity ETF with higher market risk focused on dividend growth equities. Its benchmark is the WisdomTree U.S. Quality Dividend Growth Index. DGRW had a 3-year annualized standard deviation of 10.58%. Its annualized return as of February 28, 2022, was 18.1%, surpassing the S&P 500’s return of 16.4%, resulting in an alpha of 1.7%. However, the S&P 500 might not be the ideal benchmark for DGRW since dividend-paying growth stocks form a distinct segment of the stock market and may not include the 500 most valuable U.S. stocks.

Key Considerations in Interpreting Alpha

Alpha, often dubbed the 'holy grail' of investing, demands careful consideration when applied in investment analysis.

The basic alpha calculation involves deducting the total return of an investment from a comparable benchmark within the same asset category. Thus, alpha essentially compares similar types of investments, like how the alpha of an equity ETF, such as DGRW, isn’t directly comparable to that of a fixed-income ETF like ICVT.

A more sophisticated approach involves Jensen’s alpha, which integrates CAPM theory and risk-adjusted measures. This method includes factors like the risk-free rate and the investment’s beta.

Understanding the underlying calculations is crucial when interpreting alpha values. Different index benchmarks within the same asset class can yield varying alpha results. In cases where no suitable index exists, alpha investment advisors might use algorithms and models to simulate an index for alpha comparison.

Moreover, alpha can represent the abnormal return of a security or portfolio beyond what's predicted by equilibrium models like CAPM. For example, if CAPM analysis estimates a 10% return based on a portfolio’s risk profile, but the portfolio earns 15%, the alpha would be +5%, indicating a performance above the predicted rate.

Latest Posts
Copyright 2019 - 2024