Mathematics

The Mathematics of Volatility in Video Poker

Understanding variance, standard deviation, and bankroll requirements across different video poker variants, from low-volatility Jacks or Better to extreme-variance games.

The Mathematics of Volatility in Video Poker

Volatility (or variance) measures how much results deviate from expected value over time. Understanding volatility mathematics is essential for bankroll management, game selection, and realistic expectations in video poker play.

Defining Volatility

The Statistical Foundation

Volatility is measured by variance and standard deviation:

Variance (σ²): Average squared deviation from mean

Standard Deviation (σ): Square root of variance

For video poker:

$$\sigma = \sqrt{\sum_{i} p_i \times (x_i - \mu)^2}$$

Where:

  • p_i = Probability of outcome i
  • x_i = Payout for outcome i
  • μ = Expected value (mean return)
  • Volatility Metrics

    Per-Hand Standard Deviation

    GameStandard DeviationClassification9/6 Jacks or Better4.42Low9/6 Double Double Bonus6.44Medium-HighFull Pay Deuces Wild5.08MediumNot-So-Ugly Deuces4.03Low10/7 Double Bonus5.47MediumSuper Double Double Bonus7.15High

    What These Numbers Mean

    Standard deviation represents typical deviation per hand:

  • 4.42 for 9/6 JoB: Results typically vary by about 4.4 betting units from expected
  • 6.44 for 9/6 DDB: More extreme swings—about 50% more volatile
  • Variance Components

    What Creates Volatility

    Volatility comes from paytable structure:

    Low Volatility Factors:

  • Frequent small payouts
  • Smaller jackpot premium
  • Balanced payout distribution
  • High Volatility Factors:

  • Infrequent but large payouts
  • High jackpot multipliers
  • Reduced low-tier payouts
  • The Two Pair Effect

    Comparing Jacks or Better to Double Double Bonus:

    HandJoB PayoutDDB PayoutTwo Pair21Full House99Four Aces w/kicker25400

    DDB reduces Two Pair (frequent) to fund Four Aces bonus (rare), dramatically increasing variance.

    Bankroll Requirements

    The Risk of Ruin Concept

    Risk of Ruin (RoR): Probability of losing entire bankroll before achieving goal.

    Factors affecting RoR:

  • Bankroll size
  • Game volatility
  • Bet size
  • Target duration
  • Bankroll Guidelines

    Conservative estimates for 1% Risk of Ruin:

    GameSDBankroll (5-coin bets)9/6 JoB4.423,000 units9/6 DDB6.446,500 units10/7 DB5.474,500 units

    The Royal Flush Factor

    Much of video poker variance comes from the Royal Flush:

  • Probability: ~1 in 40,000 hands
  • Contribution to RTP: 2-3%
  • Effect: Long periods "below expectation"
  • Until you hit a Royal, you're playing a losing game even on positive EV machines.

    Session Volatility

    Short-Term Expectations

    For a 1,000-hand session on 9/6 Jacks or Better:

    Expected loss: ~$2.30 per $500 wagered (0.46% edge)

    Standard deviation for session:

    $$\sigma_{session} = \sigma_{hand} \times \sqrt{n} = 4.42 \times \sqrt{1000} = 139.8 \text{ units}$$

    Practical meaning:

  • ~68% of sessions fall within ±139.8 units of expectation
  • ~95% fall within ±279.6 units
  • ~99.7% fall within ±419.4 units
  • Winning Session Probability

    Even on negative EV games, winning sessions are common:

    Session LengthProbability of Winning100 hands~48%500 hands~46%1,000 hands~44%5,000 hands~38%

    Short-term variance overwhelms small house edge.

    Multi-Hand Volatility

    How Multi-Hand Affects Variance

    Playing multiple hands changes volatility profile:

    Total session variance:

    $$\sigma_{multi} = \sigma_{single} \times \sqrt{hands}$$

    Per-deal variance:

    Increases with number of hands

    Triple Play vs. Single Hand

    Same initial hand dealt across multiple lines:

    MetricSingleTripleBet per deal5 coins15 coinsResults per deal13Per-deal varianceStandard~1.73×Session varianceStandard~1.73× for same deals

    The 100-Play Extreme

    100-hand games create massive volatility:

  • Per-deal standard deviation: 10× single hand
  • Royal Flush across all hands: Life-changing
  • Complete miss on good draw: Devastating
  • Not for underfunded players
  • Game Selection by Volatility

    Choosing Based on Goals

    Low Volatility (Jacks or Better, NSUD):

  • Longer play sessions
  • Smaller bankroll requirement
  • Entertainment-focused
  • Lower emotional stress
  • High Volatility (DDB, Super DDB):

  • Jackpot chasing
  • Larger bankroll required
  • Thrill-seeking
  • Tolerance for losses
  • The Recreational Player

    For casual entertainment:

  • Choose lower volatility games
  • Size bets for session duration
  • Accept small steady losses
  • Enjoy the experience
  • The Advantage Player

    For positive EV play:

  • Volatility determines bankroll requirement
  • Higher volatility = more capital needed
  • Must survive to reach long-term
  • Calculate RoR before committing
  • Volatility and Strategy

    Strategy Adjustments

    Volatility doesn't change optimal strategy, but affects:

    Practical decisions:

  • Which games to play given bankroll
  • Session length expectations
  • When to quit (not mathematically relevant, but practical)
  • The Misconception

    Some players think:

    "I should play more conservatively when losing"

    Reality: Optimal strategy is optimal regardless of current session results.

    Long-Term Convergence

    The Law of Large Numbers

    Over time, results approach expected value:

    Hands PlayedResult Range (95%)1,000-15% to +14% of expectation10,000-5% to +4%100,000-1.5% to +1%1,000,000-0.5% to +0.5%

    The Royal Flush Reality

    At 40,000 hands per Royal:

  • 10,000 hands: 22% chance of hitting Royal
  • 40,000 hands: 63% chance of at least one Royal
  • 100,000 hands: 92% chance of at least one Royal
  • Until Royals normalize, results remain volatile.

    Practical Applications

    Bankroll Calculator Inputs

    Needed for accurate planning:

  • Game variance (standard deviation)
  • Expected edge (positive or negative)
  • Risk tolerance (acceptable RoR)
  • Session/lifetime goals
  • Bet sizing flexibility
  • The Conservative Approach

    When uncertain, assume:

  • Higher variance than calculated
  • Worse luck than average
  • Longer to converge
  • More bankroll needed
  • Understanding volatility mathematics transforms video poker from a mystery into a manageable mathematical challenge, enabling informed decisions about game selection, bankroll management, and realistic expectations.