Postflop Coach — free heads-up postflop poker trainer中文 · 日本語 · Deutsch
Indifference & Mixed Strategies
Lesson 8 · When multiple lines tie in EV · 26 practice questions
Practice this lesson now — 26 drills, free, no signup →Indifference
Two actions are indifferent when they have the same expected value. In a balanced game that is not a coincidence; it is how equilibrium works. A bettor who wants his bluffs called sometimes but not too often sets his bluffing frequency so that the caller's bluff-catchers win exactly the price — and then calling and folding pay the same. The caller, in turn, defends just enough that the bettor's bluffs break even — and then bluffing and checking pay the same. At those points the solver is free to mix, and the frequencies you see (50/50, 70/30) are the mix that keeps the other player from profiting, not a sign that one action is secretly better.
Example. On K♠8♦4♣2♥9♠ you hold K♥6♥ in the big blind and the button fires a pot-sized third barrel, 20 into 20. Calling 20 wins 40; you need 20/(20+20+20) = 33%. K-6 beats every busted draw and loses to every better king — a pure bluff-catcher. If one-third of the button's river bets are bluffs, calling wins 40 one time in three and loses 20 two times in three: 40/3 − 40/3 = 0, the same as folding. That is why this course accepts both answers, with call first: it keeps an opponent from bluffing you freely.
Common mistake: thinking an indifferent spot means any action is fine. Calling and folding tie here; raising does not — it folds out the bluffs and gets called by the better kings.
Nuts vs pure air
Indifference also shows up in a simpler way: when villain's actions do not depend on yours. If his range on the river is pure air that will never call a bet, a bet and a check win exactly the same pot. Betting gains nothing because nothing calls; checking loses nothing because his air cannot beat you at showdown. Any mix — always bet, always check, half and half — has the same EV. The general lesson is that a bet earns money only from the hands that react to it: worse hands that call, or better hands that fold. When neither exists in villain's range, betting is not required, and the choice can be made for other reasons, such as keeping your checking range strong.
Example. Go back to the course 7 toy model on 2♣7♦9♥J♠4♠ (pot 100) and swap the seats: now you hold the set of jacks that nothing beats, and villain's range is pure air that never calls. Bet 100: he folds and you win 100. Check: his air checks back and you win the same 100. Both answers are accepted. A real near-tie: A♠8♠ on A♦9♣5♠3♥2♣ (pot 14), out of position after the button checked the turn. A small bet gets called by worse aces and nines; a check lets the button bet worse aces thinly and bluff his missed draws into you. Both lines collect from the same hands — this course lists the small bet first and accepts the check.
Common mistake: betting the nuts automatically. A bet with the nuts only beats a check when some worse hand will call it.
Don't overfit to frequencies
Solver outputs often show a hand split between two actions, such as 70% bet and 30% check. Read that as information about the hand, not as an instruction to randomize to the decimal. A mixed hand sits near the boundary between two groups: the 70/30 hand is mostly a bet that sometimes protects the checking range; a 50/50 hand is one where both lines earn about the same. Against a balanced opponent you lose almost nothing by picking one action and playing it consistently. Against a real opponent who is not balanced, the tie breaks — and it breaks in the direction of his mistake.
Example. Back to K♥6♥ facing a pot-sized river bet on K♠8♦4♣2♥9♠ (call 20 to win 40). If one-third of the button's bets are bluffs, call and fold tie at 0. If only one bet in five is a bluff, calling is worth 40 × 0.2 − 20 × 0.8 = −8 chips: fold. If half his bets are bluffs, calling is worth 40 × 0.5 − 20 × 0.5 = +10 chips: call. The hand did not change; the opponent did. The same holds for your own bets: against a player who folds too much, bluff more; against a calling station, bluff less and value-bet thinner.
Common mistake: treating a solver frequency as a fixed rule for every opponent. Frequencies describe a balance point; once you know which way the opponent in front of you leans, exploit him.
Key takeaways
• Bluff-catcher facing a bet at exactly the price (call and fold tie) → either is correct; pick one and play it consistently, and never raise.
• Nuts on the river against a range that never calls → bet or check; nothing pays, so neither line gains.
• Mixed frequency in a solver output (70/30, 50/50) → read it as 'near the boundary', not as a rule to copy.
• Opponent who bluffs more often than the price → call your bluff-catchers; opponent who bluffs less → fold them.
• Opponent who folds too much → bluff more; calling station → bluff less and value-bet thinner.
Sample drill from this lesson
Toy model (indifference): river, pot 100 chips, you are first to act. You hold a set of jacks (effectively unbeatable here); villain's range is pure air and never calls a bet. Best action?
Board: 2♣ 7♦ 9♥ J♠ 4♠
Your hand: J♥ J♣
Best action: Check Bet
Why: ✓ You have a set — check is fine here: betting is also acceptable, but a hand this strong risks nothing by checking, and it keeps the option of raising should villain bet.
FAQ
What does indifference mean in GTO poker?
At equilibrium the opponent is often made indifferent — their bluff-catcher wins and loses the same on average, so calling and folding have equal EV. That is why balanced ranges mix actions.
When should you use a mixed strategy?
Mix when two lines tie in EV — for example betting a hand part of the time and checking it the rest — which keeps your ranges balanced and hard to exploit.
Key terms in this lesson
Range (Poker Hand Range) · Position (IP vs OOP) · Bluff Catcher · Indifference (Mixed Strategies) · Barrel (Second and Third Barrel) · Value Bet · Thin Value Bet · Calling Station
Practice all 26 questions free →Every answer in the 829-question bank is independently verified (adversarial blind-solve) before publication.