Beta and Volatility

Beta is a number that describes a stock's sensitivity to the broad market (usually the S&P 500, defined as beta = 1.0). It captures systematic risk — the part of a stock's movement explained by the market as a whole. A beta of 1.5 means the stock has historically moved about 1.5% for every 1% market move, in either direction; a beta of 0.6 means it moved only about 0.6%.

Beta sorts stocks by how they amplify or dampen market moves:

• High beta (>1): amplifies the market — bigger gains in rallies, bigger losses in selloffs. Often growth and cyclical names.
• Low beta (<1): dampens the market — steadier through swings. Often defensive sectors like utilities and staples.
• Negative beta: rare — tends to move opposite the market (some hedges behave this way).

Beta feeds directly into position sizing: a high-beta name needs a smaller position for the same portfolio risk, because it swings more when the market moves.

Beta is a quick read on how much market risk you're taking. A portfolio of high-beta names feels great in a rally and brutal in a downturn; a low-beta mix rides steadier. It's essential context for sizing and for understanding drawdowns. Its limits: beta is backward-looking, can change over time, and ignores company-specific risk — so pair it with total volatility, not use it alone.

Entry Point Trading factors how much a name actually moves into its daily read, so signals are framed against real volatility — then graded in the open.