Closing line: The most important metric in sports trading

As part of any form of investing it is important to have a benchmark that you can compare your performance against. Otherwise, you do not know whether the results you are getting are because you have made smart decisions or luck. Professional poker players use analysis software to track their hand history, enabling them to review whether they make decisions with a positive expected value. E.g. calling hands where they have pot odds. For stock investors, a suitable benchmark is how you perform against the S&P 500, an index fund consisting of the 500 US companies with the highest market cap (Stock price x volume of shares). For sports traders, the benchmark is the odds at the time the match kicks-off, what is known as the closing line.

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