What is Beta?
Definition
Beta measures a stock's volatility relative to the overall market. A beta of 1.0 means the stock moves in line with the market. A beta above 1.0 indicates higher volatility than the market, while a beta below 1.0 indicates lower volatility.
Detailed Explanation
Beta is a key concept in the Capital Asset Pricing Model (CAPM) and modern portfolio theory. It is calculated using regression analysis, comparing the stock's returns against the market's returns over typically 3-5 years.
A beta of 1.5 means that historically, when the market goes up 10%, the stock tends to go up 15%. High-beta stocks include many technology companies, while low-beta stocks include utilities and consumer staples.
Beta is used in the CAPM formula: Expected Return = Risk-Free Rate + Beta x (Market Return - Risk-Free Rate). Higher-beta stocks should provide higher expected returns to compensate for additional risk.
However, beta has limitations. It is backward-looking, measures only systematic risk, and can change significantly over time. During market crashes, correlations tend to increase, making beta less reliable.
Formula
Beta = Covariance(Stock Returns, Market Returns) / Variance(Market Returns)Example
A technology stock with a beta of 1.8 will tend to amplify market movements. If the S&P 500 gains 5%, this stock would historically be expected to gain approximately 9% (5% x 1.8).
Frequently Asked Questions
What is a good beta for a stock?
Can beta be negative?
Is beta the same as risk?
Related Terms
Market Capitalization
Market capitalization (market cap) is the total market value of a company's outstanding shares of stock. Calculated by multiplying the share price by the total number of shares, it represents the market's consensus valuation of a company's equity.
Short Interest
Short interest is the total number of shares of a stock that have been sold short by investors but not yet covered or closed out. It indicates bearish sentiment and is reported as a number of shares or as a percentage of the total float.
Volatility
Volatility measures the degree of variation in a stock's price over time. Higher volatility means larger and more frequent price swings, indicating greater uncertainty and risk. It is commonly expressed as the annualized standard deviation of returns.
Moving Average
A moving average is a technical indicator that smooths price data by calculating the average price over a specific number of periods. It helps identify trends, support and resistance levels, and potential buy or sell signals by filtering out short-term price noise.
See It in Action
Disclaimer: The information on this page is provided for educational and informational purposes only and does not constitute investment advice. AI-generated analysis may contain errors or inaccuracies. Always conduct your own research and consult a qualified financial advisor before making investment decisions.
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