Forum adverts like this one are shown to any user who is not logged in. Join us by filling out a tiny 3 field form and you will get your own, free, dakka user account which gives a good range of benefits to you: No adverts like this in the forums anymore. Times and dates in your local timezone. Full tracking of what you have read so you can skip to your first unread post, easily see what has changed since you last logged in, and easily see what is new at a glance. Email notifications for threads you want to watch closely. Being a part of the oldest wargaming community on the net. If you are already a member then feel free to login now.

Anyone know of/have one (besides thier calculators)

Excel

I've written a few simple ones, it's really not that hard to do. I had one that allowed you to plug in a number of shots, a S, an AP, and it'd show the results against various troops, and against various AVs.

I've considered writing more sophisticated ones, but you pretty quickly get into special rules, needing an army list built into it, etc.

Gauss weapons, Rending weapons, how do you deal with Flamers and Blast weapons? It gets pretty complicated and pretty ambiguous pretty fast.

The basic "18 shots, two thirds hit, one half wounds, one third saves, equals 2 wounds" thing... That's not too hard. The special rules, simulating close combats with Initiative factored in... It's more complicated, and less valuable (who gets charge, etc).

Second Excel with formulas. I made one with 3 seperate zones: Ranged kills, CC kills, Plasma overheat kills. Each one has drop downs for things like Rending, Open-Topped, Melta, and such.  I'm still working the math for templates but it's getting insane! I can do one blast against known squad size and average space between models, but multiple barrage is making me reach back to high school trig, and without the threat of bad grades it becomes harder for me to finish the calculations and easier to just look up internet porn.

Can you make one that will give histograms of probabilities? I don't like the quick way of doing it because it ignores any variability in the effectiveness of weapons. 2 weapons cause the same number of mean casualties, but if the variance is bigger on one than the other it can affect whether or not it's a better weapon.

I'm not sure if you were directing that toward me MattBaby but I'll answer it anyways! My stats are per turn, or per phase stats. Now I also have a historical breakdown on unit effectiveness including their weapon loadout, opponent and other nerdy info. This is to calculate combat effectiveness of units against certain opponents, armies, and scenarios. This info is also used to calculate my battlefield analysis records. In other words, how effective is an IG mortar squad? By the stats, they suck. By the Battlefield analysis they're OK.

Probabilities are usually not what people are interested in, but they are far more valuable in calculating a battlefield analysys of a unit or weapon. For instance:

A unit of 12 firewarriors firing at a unit of 5 tac marines who can't fire back (because of the range difference in their weaponry).
A raw bench calculation looks pretty good, but there are a ton of other pieces that must fall pefectly into place for this scenario to even happen.
The firewarriors didn't move this turn.
The Marines are the closest unit.
If they aren't the closest unit the firewarriors pass their Ld test.
All 5 marines are in range of all 12 firewarriors.
All 5 marines are in LOS of all 12 firewarriors.

Assuming 25% of the table is covered by terrain and a few other things my own calculation of this event even occuring is about a 9% chance. Once it has occured THEN we can go on to calculate how many kills the firewarriors will statistically score on the marines (w/o marker 1.33, w mrkr 1.78, w 2mkr 2.22).

Back on track, the battlefield analysis will also illistrate how great a weapon or unit is based on surviveability. For example:

A lascannon fired by a guardsman in a ten man squad will be safe from morale checks until 3 guard have been killed and the unit will probably not run if it's got an officer nearby, or vet sarge, or COD. So a Lascannon will be able to to fire for at least four turns causing damage to marines.

By my own battlefield analysis, a unit like that will have been charged by turn 3 and either left unable to function to full combat effectiveness or be simply destroyed for the rest of the game. So I can typically get off 2 shots with a lascannon which statistically means I will hit and kill one marine before the unit is no longer able to fire due to assault, destruction or target availability.

Keep in mind that all of my battlefield analysis are based on my own games and games that are played around here so if your common opponent is tyranids you should tailor your stats accordingly.

Posted" by="" glaive="" company="" co="" on="" 04/17/2006="" 2:21="" pm="">
I'm not sure if you were directing that toward me MattBaby but I'll answer it anyways! My stats are per turn, or per phase stats. Now I also have a historical breakdown on unit effectiveness including their weapon loadout, opponent and other nerdy info. This is to calculate combat effectiveness of units against certain opponents, armies, and scenarios. This info is also used to calculate my battlefield analysis records. In other words, how effective is an IG mortar squad? By the stats, they suck. By the Battlefield analysis they're OK.

Sorry, I was unclear in asking my question. Consider a team of 10 Fire Warriors. Now, a single BS3 shot from a pulse rifle has an 11% chance of killing a Marine. Multiplying an outcome with an 11% chance of success suggests that 1.1 marines should be killed. However, that statement lacks mathematical rigour. If we shoot enough Pulse Rifles, eventually we should expect the number to approach 11% dead marines per shot fired and then not deviate from that. However there's no garuntee that firing 10 pulse rifle shots will kill 1 marine (and a servitor or something, the 1/10). A more rigorous model (which should be possible in Excell, though I haven't done it myself) should be enough to reveal ALL probabilities. For example, the possibility that ALL TEN shots hit and kill the Marines is 0.000000002867%. The possibility that not a single Marine is killed is 30.79%. There are another 9 possible outcomes, each with a variety of probabilities. Is there a way to calculate all 11 possible outcomes all at once? This allows for calculations of reliability (which is just another way of saying variance) as well as mean damage.

Yes, there is a simple way of doing this.  Look up the binomial distribution on google, and you should quickly find the equations for working out the probability of n successes in x trials with each trial having probability p of success.  There's also a simple formula for at least n successes.

Ahh, I see what you're talking about now! Sorry to ramble on like that without even answering you're question! It sounds like spikydavid's on to something there although (like you said) it can be done with excel pretty easily. For my plasma overheat kill section it sort of breaks down that way. It calculates the percentage of killing the firing model compared to killing the target.