## Probability

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Probability is a word that most people have heard and that almost everybody has a general idea about regarding the definition of it.  However, not many people actually realize the true power of probability.  Even if you know the chances of a coin flip are 50/50 or 50% (because there are 2 evenly probable ways it can land (1 or the number of ways to win, divided by the number of possible outcomes in this case because the 2 possible outcomes have an even chance of occurring,)) you also are likely aware that if you flip a coin 10 times, it can and often does come out 9 heads and 1 tails or 3 heads and 7 tails etc.  The real interesting thing about the 50% probability of a fair coin flip is that if you flip the coin more often, the results will more closely resemble the 50% probability of the event occurring. So if you flip the coin 100 times, it’s more likely to be closer to 50 heads and 50 tails than 5 and 5 for 10 flips.  And with 1000 flips, it’s even more likely to be closer to 500 and 500 than the 50 and 50 or the 5 and 5.  This concept is called the Law of Large numbers.

So most of us would not intuitively think about this being the way the world works, or about how you can put an actual number on something that will tell you what will occur how many times because we think about all those times where it doesn’t or won’t occur.  We are not use to repeating the same exact thing 1,000 or more times.  We think about the chances on a surface or in a general sense but do not think much about how over enough time, these chances if measured correctly, always come into fruition.  With enough repetition, knowing the probability is a way of telling the future.  People who know how to compute the probability of various games and their payout structures, are able to use this ability of telling the future to make money from the game over time if they have a strategy that forces the game to pay out an amount over time that Is favorable to the player over time given the probability and odds of such an event occurring.

In 6 sided dice, it can come out 6 different even ways because there are 6 sides with even chances of landing up, so the odds or chances are 1/6. In a deck of cards, there are 52 cards so the chances or probability of getting any one specific card is 1/52 which can be read as 1 in 52 or 1/52 or divided as approximately 1/52 = 0.01923 (around 1.9%). There are 4 different suits (hearts, diamonds, spades, clubs) with 13 cards in each suit so the chances of drawing a card of a specific suit from a full deck are 1/4 or 0.25 or 25%.  If you Know you have a 25% chance of drawing a card of one type of suit and you find a game that requires you to guess the suit of a card being drawn from a full deck of cards (with no jokers,) 3 to 1 odds (you pay 10 dollar for a chance to win 30 plus your 10 back) is the point at which it’s a completely fair game.  Anything that pays more than that will be profitable over time if you size your bets in a way that allows you to continue betting a portion of your bankroll long enough for the 25% probability to come into fruition.  3.01 to 1, 3.10 to 1, 4 to 1: any of these would turn a profit if bet properly and enough times.  You could get lucky and turn a profit after 1 or 5 turns but over time, you would no longer need luck and you would just be paid from knowing the math behind how the game works and recognizing the payout structure as being favorable compared to these odds.

In games where the true odds can not be known like sports betting, you can sometimes estimate the likelihood of an event occurring and still find the same type of edge in a discrepancy between what it would pay if completely fair and what it pays below what you think the true chances of the event approximately are.  In cases like this where you’re estimating, it is best to leave some wiggle room or margin of error so that you are only placing wagers when your estimated percentage is far above what the fair payout percentage is in the implied percent chance of the payout odds.  To find out where you have this type of edge, you can learn the math, get a chart with the payouts and implied percentages or use one of the available calculators for such things online. 