| View previous topic :: View next topic |
| Author |
Message |
longarms
Seasoned
Joined: 02 Oct 2007
Posts: 129
|
 Posted: Wed May 23, 2012 9:00 pm Post subject: savage odds on opposed rolls |
 |
|
Would anyone that knows address how to determine the odds of succeeding on an opposed roll (and the odds of getting a raise).
Or if there is some resource somewhere... point me to it? Thanks! |
|
| Back to top |
|
 |
robert4818
Heroic
Joined: 25 Jan 2009
Posts: 1044
|
| Posted: Wed May 23, 2012 11:43 pm Post subject: Re: savage odds on opposed rolls |
|
|
| longarms wrote: | Would anyone that knows address how to determine the odds of succeeding on an opposed roll (and the odds of getting a raise).
Or if there is some resource somewhere... point me to it? Thanks! |
Combinatorics for it are not pretty.
Basically, you have to figure out every combination of between 2 to 4 dice (depending on whether each side is extra or wild card.)
For example, for a wild card vs a wild card.
You need to find every combination of Dx D6 vs Dy D6 and count how many times you win, divided by the total number of combinations. x*y*6*6. Of course this gets trickier since the dice explode.
Its not an easy thing to do.
_________________
Aperture Science:
We do what we must, because we can. |
|
| Back to top |
|
|
ValhallaGH
Legendary
Joined: 25 Apr 2010
Posts: 4455
|
| Posted: Thu May 24, 2012 9:03 am Post subject: |
|
|
You can speed it up, a lot, by using the Savage Worlds Probability Calculator. Input the TN (assume the foe got that as their result) and see the odds of success, raise, failure, and critical failure. Handy, accurate and fast.
How to Calculate Success:
The basic success formula for a trained skill is (1 - [ 9 / (6 * x)]), where x = the trait die type. More generally, that's going to be:
1 - (3 / 6) * (3 / x)
Because the d6 will fail 3 / 6 times (TN 4), and the dx will fail 3 / x times (TN 4). The total failure rate is the multiple of those two (9 / 6x), and the success rate is ( 1 - failure).
If the effective TN is not 4, then you'll have to figure out what the failure rate for each die type is (for "TN 6", d6 will fail 5 / 6 times; d4 will fail 13 / 16 times; d8 will fail 5 / 8 times; etc). Plug that new failure rate in and you're ready to rock.
If calculating the chance of a Raise and only a Raise, then the effective TN is 8.
The problem you've posed is that the TN is a variable. That makes it impossible to calculate a discreet result - you'll end up with a range of results, probably derived via calculus.
_________________
"Got a problem? I've got the solution: Rocket Launcher."
"Not against a Servitor."
"... We're all gonna die." |
|
| Back to top |
|
|
shinryu
Seasoned
Joined: 18 Jul 2011
Posts: 300
|
| Posted: Sat May 26, 2012 7:13 pm Post subject: |
|
|
| The best option in this case might be simulation: you program something up to roll the dice 10,000 times and figure the probability of either side winning from the results. It should be a 50/50 for matched die types, but I'm not rightly sure how well using the odds vs. a given TN approximate the actual results for other combinations. If you're a coder this is trivial to do, but if not I have a few R scripts sitting around for this I can run and get back to you. Any particular combination interesting? All the Wild Card possibilities vs. one another? |
|
| Back to top |
|
|
longarms
Seasoned
Joined: 02 Oct 2007
Posts: 129
|
| Posted: Sun May 27, 2012 1:11 pm Post subject: |
|
|
How about wild cards vs. an extra of the same die type?
So d4 wild card vs. d4 extra, d6 wild card vs. d6 extra, etc.
Also, how about d8+2 wild card vs. d8 extra.
PS - remember tie goes to the defender. Can you add that to your script? I mention this because you threw out 50/50 on equal die... I get its more like 40/60 on equal die because the tie goes to the defender. |
|
| Back to top |
|
|
ValhallaGH
Legendary
Joined: 25 Apr 2010
Posts: 4455
|
| Posted: Sun May 27, 2012 1:32 pm Post subject: |
|
|
| longarms wrote: | How about wild cards vs. an extra of the same die type?
So d4 wild card vs. d4 extra, d6 wild card vs. d6 extra, etc. |
The extra has a 1 / X of any given result, while the wild card has a Y / (6*X) of getting the same result. Odds should massively favor the Wild Card.
| Quote: | | Also, how about d8+2 wild card vs. d8 extra. |
Again, the odds should massively favor the wild card, especially due to that static bonus.
Of course, a Monte Carlo simulation is really the only practical way to get the odds on this sort of thing. And that's a very brute force solution, and one I'm not set up to run anytime soon. But someone around here (sorry, I have terrible memory for names) does that for combats, so maybe we can get him to crunch the numbers for you quickly.
_________________
"Got a problem? I've got the solution: Rocket Launcher."
"Not against a Servitor."
"... We're all gonna die." |
|
| Back to top |
|
|
Energy
Novice
Joined: 30 Jan 2012
Posts: 30
|
| Posted: Sun May 27, 2012 4:27 pm Post subject: |
|
|
I made a chart for a previous discussion, let me link it for you.
| Quote: | 
So that shows how wildcards with various active dice do against extras, both their chance to simply win the opposed roll and win with a raise. So if you were a wildcard with a d10 in taunt, a -2 penalty to your roll and went against an extra with a d6 in Smarts, you would taunt him 53% of the time and shake him 26% of the time. When I put together the chart, I didn't subtract out the raise % from the success %, so don't read that as "I get something done 79% of the time," all those raises are also counted in the simple success column.
There's also a Fighting row, which shows the unmodified chance to hit or raise vs an opponent with that particular level of fighting. So a wildcard with a d8 in fighting, will at least hit an opponent with a d6 (and therefore parry 5) 67% of the time.
|
|
|
| Back to top |
|
|
longarms
Seasoned
Joined: 02 Oct 2007
Posts: 129
|
| Posted: Mon May 28, 2012 5:43 pm Post subject: |
|
|
| thank you very much! |
|
| Back to top |
|
|
|
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
