A mathematical theorem that states, for any set of independent random variates with finite variance, that the cumulative distribution function of a normalized (scaled) sum of such variates approaches the cumulative distribution function for a normal distribution, as the number of variates increases. Under certain circumstance, the theorem states that the width of the central region of the associated probability distribution function narrows, and approaches zero, as the number of random trials (variants) increases and that the shape (of the central region) of the PDF approaches a normal PDF as the number of trials increases. If all variates are from a single uncorrelated random process, the theorem states that variance decreases as 1/sqrt(n) where n is the number of trials. Since each video poker hand is independent of all other hands, and since video poker's variance is finite, The Central Limit Theorem holds for all video poker, and the variance scales as 1/sqrt(n), where n is the number of hands. However, at the same time, the total bet or coin-in has been increasing proportional to n. Thus the variance in real units (dollars) increases without limit as the player continues to gamble.
See also: PDF, Coin-in, Variance, Central Limit.

Gambling strategy that seeks to maximize the games return. Also know as Max-ER strategy, this is by far the most common gambling strategy. Other strategies might involve reducing risk (minimizing the variance), for example.

A function describing the probability of event occurring for all possible events. For video poker, the set of events are precisely the possible winning hands along with "nada" the event for a non-winning hand. The probability of each winning hand (and nada) depend on the strategy, and can be obtained by numerical simulation or direct computation (hand enumeration). From the Probability Density Function, one can compute the game return and variance (that is, from the first and second moments).
See also: Cumulative Distribution Function.

The probability that, given a certain bankroll, a gambler will be ruined. For video poker, the Risk of Ruin is generally computed for an infinite number of hands, since the computation easier, though it can also be computed for any number of hands. However, if the number of hands is not specified, it is assumed to be infinite. The (infinite run) Risk of Ruin is always greater then zero for video poker, including positive games, since the variance is always non-zero. For all negative expectation situations, the Risk of Ruin is always 100%. That is, regardless of the bankroll, a gambler who plays a bad game will eventually go broke. The Risk of Ruin decreases as the size of the bankroll in betting units increases. Hence, decreasing game denomination (unit or wager) at a fixed bankroll decreases Risk of Ruin.
See also: Survivability.

The (positive) square route of the variance. The Standard Deviation can therefor be in units of the bet.
See also: Variance.

A video poker game in which the wagering of a sixth coin (assuming the base game is a five coin max game) triggers a new mode that gives the player a bonus whenever there is a (natural) four of a kind. The average bonus is approximately 428 units, and it increases the return (relative to the base game) of all video poker games except for (most) wild card games, such as Deuces Wild. The Wheel Poker feature increases the variance of games and necessitates strategy changes to achieve the best return.