AP Glossary
WhatIsVariance?
The natural fluctuation of actual results around the expected value. High variance means bigger swings between wins and losses. Even +EV plays can produce losing sessions due to variance — bankroll management accounts for this.
Why It Matters
Why this matters for advantage play
Variance is what makes slot AP feel nothing like the math says it should over short windows. Internalize it early or you'll mistake bad luck for bad strategy and abandon plays that were correct.
Variance GuideCross-Reference
Related terms
Volatility
How much results vary from the expected return in the short term. High volatility slots have infrequent but large payouts; low volatility slots pay smaller amounts more often. For AP, higher volatility means you need a larger bankroll to survive the swings.
EV (Expected Value)
The mathematical average outcome of a bet calculated over infinite repetitions. Positive EV (+EV) means the play is profitable long-term; negative EV (-EV) means the house has the edge. AP players only take +EV plays.
Bankroll
The total money a player has allocated specifically for advantage play sessions. Proper bankroll management ensures you can survive the natural variance of +EV play without going broke.
Session Bankroll
The amount allocated for a single playing session, separate from total bankroll. Session bankroll limits protect the overall bankroll from a single bad variance run.
Frequently Asked
Common questions about variance
Closely related. Variance is the formal statistical measure; volatility is the practical, often game-marketed term. In casual AP discussion they're used interchangeably.
Play more sessions. Variance compresses with sample size. Single-session variance can be enormous; thousand-session variance is much tighter.
Over short windows, realized results can be deeply negative even on +EV plays. Long-run, +EV does prevail — that's the definition. The challenge is having bankroll and patience to outlast the variance.
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