Well, let's put it in gambling terms.
All events in gambling games have absolute probabilities that depend on sample spaces or the total number of possible outcomes. For example, if you toss a six-sided die, the sample space is six, with the probability of landing on any particular side one in six. Games with huge sample spaces, like poker, have events with small probabilities. For instance, in five-card poker, the probability of drawing four of a kind is 0.000240, while the chance of drawing a royal flush, the rarest hand, is a mere 0.00000154.
Skilled poker players understand the sample spaces of the game and probabilities associated with each hand. Thus, estimating the odds of a particular hand will guide their
gamble.
Adept players are interested not only in probabilities but also in how much money they can theoretically win from a game or event. The average amount you can expect to win is aptly called the expected value (EV), and it is mathematically defined as the sum of all possible probabilities multiplied by their associated gains or losses.
Generally, skilled gamblers assess the risk of each round based on the mathematical properties of probability, odds of winning, expected value, volatility index, length of play, and size of the bet. These factors paint a numerical picture of risk and tell the player whether a bet is worth pursuing.
Still, gambling involves far more than simple mathematical properties. Gamblers use a great deal of social psychology to read their fellow players. The ability to decipher bodily cues, for instance, helps discern fellow players’ mental states and possibly gives a clue to the statistics of their hands.
Gambling is an art and a science; only the best players can synthesize the two to reap millions.