Too much effort. Don't even have an accurate calculation for suppression in general, only guesstimates based on testing.
Mr Smith
I domt know how suppression works precisely to give you the answer.
Cruzz
How Suppression Works:
Penalties for suppression and pin
Penalties for firing on suppressed/pinned units
Suppression value required for suppress: 0.2
Suppression value required for pin: 0.6
Suppression value at which unit recovers from suppress: 0.15
Suppression value at which unit recovers from pin: 0.5
Suppression modifiers against cover: 0.1 green, 0.5 yellow, 1 nothing, 1.5 red.
Suppression recovery rate: 0.008 per second, multiplied by 0.5 in red, 1 in nothing, 2.5 in yellow, 5 in green
Units gain a 50* multiplier to recovery rate after 7 seconds of being out of combat.
Suppression is a squad value. Individual models don't feature into the equation except for the guy the suppressing weapon is firing on, whose cover will be used to determine the penalty applied to both regular suppression and AOE suppression. Suppression is always applied regardless of whether the bullet hits or misses. AOE suppression is only applied on hit.
Now let me explain why this is utterly broken. Because aoe suppression takes its modifier from the thing that its firing on, this means that any squad in front of green cover being shot at will make stuff behind the green cover suppress extremely fast as well through aoe suppression.
Recovery works in combat, though is clearly interrupted by some events like receiving and receiving damage. As such while it's fairly easy to keep units not in cover suppressed just by firing at them occasionally because the natural recovery speed will take quite a while to remove suppression, against units in green cover you will have to be actively doing something to them in order to stop them from recovering.
Incremental accuracy is probably +15% for every 2 or 3 models in the search area in addition to the one being fired upon. It's definitely not per each model. Takes too long to test to give a certain answer.
Fixed a bug where firing at non-infantry targets would suppress nearby infantry. Now suppression platforms will only deal AoE suppression if the primary target is an infantry model.
Q:It's not supposed to be relevant if a shot hits or misses?
A: It matters for AOE suppression which only seems to apply on hit.
Does that mean every shot fired will actually apply suppression to its target?
Yes suppression on the targeted squad will be applied whether you hit or miss.
Incremental accuracy
It certainly doesn't seem to be per entity, because making a massive stacked blob and firing at it with say an M20 (12% incremental on 20% far accuracy) will still have it miss most shots. For the time being I've been assuming that it's being calculated like this as results seemed mostly in line with my very limited testing:
while(targets/2 >= 1){
accuracy = accuracy * incremental;
targets = targets/2;}