I'm sorry to be the bearer of bad news but this "method" to determine the amount of force armor absorption/mitigation is astronomically inaccurate and is in now way even remotely close to reliable.

In order to determine the correct amount that force armor absorbs we need to determine some other data first..

If we assume the tool tip and information from Torhead accurately depicts the in game coding then

AbsorbDamage:

SpellType=>Force

StandardHealthPercentMin=>0.164

StandardHealthPercentMax=>0.164

HealingPowerCoefficient=>3.27

DamageType=>None

AmountPercent=>1

Ability Healing Min = Coefficient * HealingBonus + StandardHealthPercentMin * StandardHealth

Ability Healing Max = Coefficient * HealingBonus + StandardHealthPercentMax * StandardHealth

Standard health for all classes at 50 = 7085

Min & Max = 3.27 * HealingBonus + 0.164(7085).

to calc HealingBonus, we look at Willpower, ForcePower, and Power bonuses

Bubble = 3.27 * [0.14(WP) + 0.17(FP) + 0.17(P)] + 0.164(7085)

now in PvP, since expertise healing bonus is technically trauma ignore, not throughput bonus I'm assuming that expertise doesn't affect the amount of absorb that a bubble has.

so you get a nice simple equation to plug your own toon's stats into.

Bubble = {3.27 * [0.14(CasterWP) + 0.17(CasterFP) + 0.17(CasterP)] + 0.164(7085)} + 20 * {1 - [ 1 - ( 0.01 / 0.2 ) ]^[( TargetExpertise / 50 ) / 0.72 ] }

Hope this clarified some of your confusion on force armor

Im not asian