Beta: Difference between revisions

{{a|glossary|}}So-so. Ordinary. Unspectacular. Safe. Dull. Meets expectations. Won’t try to rip you off.  

Defined in a famous paper by William Sharpe in 1964 — he of the [[Sharpe ratio]] — [[beta]] is defined as  

''“a portfolio risk that cannot be diversified away by adding more securities to it.”''

Since the whole market has all the securities in it, you can’t add to that, the whole market has a beta of 1. Therefore, to track [[beta]] is to track the whole market’s performance. Therefore watch out for — well, to put not to fine a point on it — ''bullshit'' products claiming to yield returns like “[[intelligent beta]]”; “[[smart beta]]” or “[[enhanced beta]]”. Nonsense on stilts.