[Rigelian]

Your system makes all bonuses/penalties have less effect at long range than they do at short range though. A 20% penalty to hit from the enemy having ECM I currently gives you a to hit chance of 80%, modified by range. In your system, you get to hit chances like this with a range 10 weapon:

range 1: 1.0 * .80 = .80
range 2: 0.9 * .80 = .72
range 3: 0.8 * .80 = .64
range 4: 0.7 * .80 = .56
range 5: 0.6 * .80 = .48
range 6: 0.5 * .80 = .40
range 7: 0.4 * .80 = .32

So, at range 1, the ECM provides a 20% to hit penalty (from 100% to 80%). At range 5, it provides only 12% to hit penalty (from 60% to 48%). Your system makes the ECM less effective at longer ranges, which does not make any sense (being counter-intuitive and all). The same thing applies to all other modifers too. They are not supposed to provide variable bonuses, but constant bonuses.

This is the absolute heart of the disagreement here. Because I regard that effectiveness as being exactly the same _relative_ chances to hit with or without ECM.
So at range 1, if I fit ECM to my ship the enemies chance of hitting me is 0.8 times what it was...(80% / 100% )
At range 5 the enemies chance of hitting me is 0.8 times what it was... (48% / 60% )
At range X ... and so on.

You see the result as different because you are subtracting the percentages, and I think that is incorrect.

This requires that the to hit modifiers be very strictly limited to only a few input values, instead of all possible modifiers just being added to the to hit chance. It also unnecessarily complicates the calculations, while granting counter-intuitive effects.

But what do you think of the idea of a 'to hit' chart then? Base chance to hit depends on range _and_ weapon, all modifiers to that based on multiplicative maths.

I know how algebra works...

Converting a percentage to a decimal probability value is completely irrelevant to this argument. That one operation of division in no way makes the se4 system have mixed operations. All chances to hit are added, there is no multiplication in them.

No offence intended, and I had assumed you did. I only decided to define my terms when we moved this back to the public forum. I disagree on the relevance because a percentage and a decimal probability are synonymous in my view, and this implies that percentages should never be added, only multiplied.

Also, how would you propose to implement both ECM and Combat Sensors? Which gets priority? Say both have a 20% modifier. Base chance to hit is, say, 80%.

Do CS first, then ECM (the other way gets the saem answer):
.80 * 1.2 = .96
.96 * .80 = .768

With either method, the 20% bonus and 20% penalty do not cancel each other, and you are left with an overall penalty to hit, even though you have the same power of ECM and CS. You would have to very carefully calculate the values of ECM and CS to make sure that they actually cancel each other, and not end up with stupid results like getting an overall to hit penalty. Or, you have to add the .2 and -.2 to the base 1.0 modifier, which results in using additive properties again. The current SE4 system does not have any of these problems. They become more severe when you start adding even more factors to the calculation (various armors, training, racial bonuses, facility bonuses, etc.)

The additive system allows for more bonuses and penalties to be applied at the same time without making the mathematics unnecessarily complex.

The percentage to hit is indeed a probability, but the method of acheiving the final probability currently used in SE4 allows for more flexibility and more options.

I would implement them exactly as you have calculated, because I don't regard that as a stupid result, but a correct one. But I completely agree that the vast majority of people would not find that intuitive, and would expect a 20% bonus to cancel a 20% penalty. But ask the majority of people what 80% of 120% is and I suggest that they would get it wrong. That is, I guess, sufficient argument when we are talking about a game, not putting people on Mars here..

Agreeing to disagree on the additive modifiers then, what about 'to hit' charts? Base chance to hit depends on range _and_ weapon, all modifiers to that based on (multiplicative/additive) maths. I'd be interested in your views on that, because whether you add or multiply there is a huge 'edge effect' at maximum range with standard 10% penalty per square.

Rigelian