Originally posted by mkjmkjmkj
but im mostly asking if we should bet small because we want be called by worse hands that would fold to a big bet because villain is affraid of the flush or if its better to bet big to charge draws.
It will be very opponent dependent but basically you just have to assess how their range looks on the turn vs different bet sizes.
Just to give an example
Say you have 2pair and pot is 25bb on the turn, and villain called flop w lets say 120 combos of hands, some of which are pairs, some of which are drawing. Let's assume he doesn't raise the draws he's hit and just calls to make things simpler.
When villain folds you win 25bb, when he calls a worse hand you win 25+Xbb and when he calls a better hand you lose Xbb. Where Xbb is your betsize in bb
Betting 6bb lets say he calls 95/120 combos, 12 of which beat you.
Villain folds 25, loses 83 and wins 12 combos.
(25/120)*25+(83/120)*31-(12/120)*6
On average betting 6bb wins you 26.05bb against this range
Betting 12bb he might call 64/120 combos, 12 of which beat you.
Villain folds 56, loses 52 and wins 12 combos.
(56/120)*25+(52/120)*37-(12/120)*12
On average betting 12bb wins you 26.5bb against this range
Betting 25bb he might call 32/120 combos, 12 of which beat you.
Villain folds 87, loses 20 and wins 12 combos.
(87/120)*25+(20/120)*50-(12/120)*25
On average betting 25bb wins you 23.9bb against this range
This is ignoring what may happen on the river also, because this complicates things a lot.
Vs any opponent they will have different calling ranges vs different bet sizes. Some opponents will call the same amount of hands regardless of the bet sizes.
Obviously you can't do this in-game, but looking at these spots with assumptions about ranges can help you to understand how to play against certain opponents in certain spots, and once you know this, you can extrapolate from these calculations in similar spots.