Sports statistics regularly use the theory of probability. It is important to have a good grasp of the concept in order to use the information appropriately and understand the meaning behind it. The starting point in sports probability is an experiment. An experiment is any course of action where the outcome is random. An experiment can be very general such a football game or more specific such as the quarterback throwing a pass to one of his receivers.
Once the type of experiment has been determined, the next step is looking at the specific events. Events are the outcomes of the experiment. In terms of the football game, the event could be the final score, the number of passing yards, or the number of passes attempted. In terms of the quarterback throwing a pass, the event could be whether it was a success or failure or the number of yards gained.
Each event has a corresponding probability. Probability is defined as a measure of how often a particular event will happen the experiment is done repeatedly. Probability tells us what will occur in a theoretical situation. If you toss a coin an infinite number of times, you will get heads 50% of the time. However, if you toss a coin only twice you are not guaranteed to get a head once and tails once. Therefore, a probability is not a guarantee of an outcome, but an indicator of what should happen if everything follows the same pattern as it has in the past.
At times, we might want to look at the probability that something will not happen. This is found by subtracting the probability that it will happen from 1.
The chance that an event will happen is most often expressed as probability. However, sometimes it is easier to use odds rather than probabilities. To find the odds of an event happening you take the probability of that event happening and divide it by 1 minus the probability of the event. When probabilities are very small or very large they become unwieldy to work with and difficult to interpret. In these instances, it is easier to work with odds rather than probabilities.
When odds are used within the world of sports, they are able to indicate the relative difficulty of an event. The greater the odds the harder it is for success to be achieved and consequently is less likely to occur.
Analysts use probabilities and odds to make predictions regarding outcomes of games and the performance of various players during the game. Coaches use probability as a tool to determine what areas their team needs to work on in order to increase the probability of success.
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