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Ok.. so I was bored.. I wanted to know at what skill check percentage I was going to average the most experience. I realized the equation for this was a curve and instead of doing it the easy way I did basic Calculus for the 1st time in almost a decade (See mom, that college education isn't going to waste ). It turns out you get the best results at a 50% check earning on average 87.75 xp per check. The top of the curve is pretty flat so anything close to 50% gives almost as good a result.









here's some average xp for skill check %s if anyone cares

• 2% ~7xp
• 20% ~53xp
• 30% ~73xp
• 40% ~84xp
• 50% ~87.75xp (max)
• 60% ~84xp
• 70% ~73xp
• 80% ~53xp
• 98% ~7xp or ~16xp* or ~25xp**

*at 88+% there may be a boundary limit that starts kicking in (assuming you can't get negitive xps from a succussful check.. Larkin?) If this limit exists then the numbers at the very top of the scale (88+%) don't drop off quite as rapidly as the ones at the bottom, hence the ~16xp at 98% assuming I did the math for the boundary limit correctly.

** see post further down, Clarification of minimun xp from a successful skill check yields ~25xp (this is the 'real' value)

*Coyote raises a glass to number-crunchers and bean-counters everywhere.

Nice.

So I guess it pays to be good... but not too good.

widowmaker

Sleeping_Dragon wrote: *at 88+% there may be a boundary limit that starts kicking in (assuming you can't get negitive xps from a succussful check.. Larkin?) If this limit exists then the numbers at the very top of the scale (88+%) don't drop off quite as rapidly as the ones at the bottom, hence the ~16xp at 98% assuming I did the math for the boundary limit correctly.

int CalcXps(int check, int toss)
{
int ret;


ret = 375 - (3 * check) - toss;

if ( ret < 15 )
ret = 15;

return ret;
}

I think it's time to give Larkin another break, he's started speaking in code .

widowmaker wrote:So I guess it pays to be good... but not too good.

widowmaker

Skill check %s and skill values are 2 different things...
Also notice that those are averages, which might be misleading.
Finally, it only takes into account "visible" skill checks, which are only part of the whole.

Thanks to Larkin's little code tidbit, the minimum xp for a succussful skill is 15xp. That changes the boundary conditions from what I'd guessed. The real boundary limit will start kicking in at 84% and at a 98% check the average xp will be ~25xp.


As Iceman pointed out these are AVERAGES for skill check percentages NOT your skill value %.

Always remeber.. Figures don't lie; but liars can figure Always know EXACTLY what the numbers are discribing it may not (usually) be what it appears at first glance.

LarkinVB wrote:int CalcXps(int check, int toss)
{
int ret;
ret = 375 - (3 * check) - toss;
if ( ret < 15 )
ret = 15;
return ret;
}

Cool. I had wondered what language was used to write the game, and that looks suspiciously like C++. I know not all of the game is in C++; what other languages were used? If you don't mind my asking, of course.

widowmaker

Thorgrim wrote:--------------------------------------------------------------------------------
Originally Posted by widowmaker
So I guess it pays to be good... but not too good.
--------------------------------------------------------------------------------

Skill check %s and skill values are 2 different things...
Also notice that those are averages, which might be misleading.
Finally, it only takes into account "visible" skill checks, which are only part of the whole.

I winked! Is joke. Laugh.

widowmaker

widowmaker wrote:Cool. I had wondered what language was used to write the game, and that looks suspiciously like C++. I know not all of the game is in C++; what other languages were used? If you don't mind my asking, of course.

widowmaker

Since you seem to have interest

1. No, its not C++ but you are close. After C++ do C-- and you have it
2. Its only written in one language. So how do you know another language is involved ?

So based on the formula that Larkin posted, wouldn't a 25% skill roll always produce better XP than a 50% skill roll?

375 - (3*50) - (1thru100) = 224thru125xp

where

375 - (3*25) - (1thru100) = 299thru200xp

I was assuming that you only get XP when the skill roll is sucessfull, is that true or do you get it everytime a roll is made?

Yes, because it's a harder skill check. You won't make the check as often, but when you do you'll get more XP. Hence the warning in my post above... actually, it won't *always* happen in your own example, 224/200 for example. But for the same toss, yes (up to 25%).
And that is correct, you only get XP when you succeed.

MahaROGa wrote:So based on the formula that Larkin posted, wouldn't a 25% skill roll always produce better XP than a 50% skill roll?

375 - (3*50) - (1thru100) = 224thru125xp

where

375 - (3*25) - (1thru100) = 299thru200xp


I was assuming that you only get XP when the skill roll is sucessfull, is that true or do you get it everytime a roll is made?

Yep, you will get more xp for a SUCCESSFUL check at 25% then you would at 50%.. BUT you only successfully make that check 1/2 as often.

also in your examples:
375 - (3*50) - (1thru100) = 224thru125xp...

not quite true.... cause any die roll over 50 is a failure which gives you 0xp... so

375 - (3*50) - (1thru50) = 224thru175xp (51thru100)=0xp
and 375 - (3*25) - (1thru25) = 299thru275xp (26thru100)=0xp


look at the 2% check it's an easy example.. its only ~7xp on AVERAGE... if you make a 2% check you'll earn either 368 or 367xps on a roll of 1 or 2, but you'll only earn that 2% of the time, the other 98% of the time, for rolls 3 thru 100, you get SQUAT so for a 2% check.. it's (368+367+0+0+0...+0*)/100 = 7.35xp AVERAGE.
* thats 98 +0s



BTW the formula to deterine the average xp for a given % skill check is (n/100)*(375-(3*n)-((n+1)/2)) where n = the skill check number (ie. for 2% n=2) (this only holds for 83%(?.. see below) and below because of the 15xp minimum for a successful check changes things at 84%(?.. see below) and greater)


Also noticed you used 375 instead of 350 in the xp formula. then looked closer at the code Larkin posted. I used 350 instead of 375 for the numbers I posted originally. I got the 350 from the xp formula in the ToS guide that was posted but that wasn't 100% accurate. All my #'s should be slightly(?) higher and the boundary limits due to the 15xp minimum will be push up a few % and the number for 98% may be off considerably on the low side... will recalculate at a later date. Formula I posted to find average xp has already been corrected.

LarkinVB wrote:2. Its only written in one language. So how do you know another language is involved ?

Somewhere out there in a post you suggested an alternative to DirectX that was a free download. I assumed it was used for this game. Perhaps I mispoke in saying it was a language. That is what I was referencing.

widowmaker

Wait... the minimum XP for a successful check is 15? Does this translate directly to the "XPs earned" portion of the F2 screen? I was watching my XPs in a fight the other night. I had an enemy Titan down in the same hex as mine and shot it with 5 MGs. Each had a 98%, and each hit earned me 2 XP (combat XP, obviously). Are there other factors to XPs earned?

Or is this a patch update that isn't in effect yet?

widowmaker

There are some other modifiers. I know that shooting a fallen or disabled titan is one of them, I think it's half xp, but these are 'conditional' modifiers so I can't take them into account when crunching the numbers. Don't have a clue what other conditional modifiers could exsist. Although they PROBABLY cut the xp AFTER the xp for the check is determined.. so 15xp becomes 7 or 8 xp. No sure how the 2xp was determined, could be modifiers. Will pay more attention at the numbers in my next game.

Ok, re-did the numbers using the 'correct' formula (375 instead of 350) and it changes the numbers quite a bit.






The optimal check % for maximum average experience is now 53% and 54%. The boundary condition that the minimum xp for a successful skill check is 15xp doesn't start to effect the numbers till a 91% skill check. (The 98% skill check number below takes this into account)

• 2% ~7xp
• 10% ~34xp
• 20% ~61xp
• 30% ~81xp
• 40% ~94xp
• 50% ~100xp
• 53% and 54% =100.17xp (max)
• 60% ~99xp
• 70% ~91xp
• 80% ~76xp
• 90% ~54xp
• 98% ~36xp

Thanks for the explaination BBlue. I didn't understand that you were trying to determine the average XP over the average roll for each skill value. But on my way home I did finally understand what you were doing and your note confirmed that.

I'm surprized that this seems to produce a curve (except for the minimum of 15xp) I would have expected it to be linear. Maybe it's a triangle rising up to 50% and then declining.

Anyhow... Kind of interesting, not sure how useful it is... I'm certainly not going to try to shoot while moving just because that gives me a 50% roll vs. the 75% roll that I would get if I stood still.

MahaROGa wrote:I'm surprized that this seems to produce a curve (except for the minimum of 15xp) I would have expected it to be linear. Maybe it's a triangle rising up to 50% and then declining.

Anyhow... Kind of interesting, not sure how useful it is... I'm certainly not going to try to shoot while moving just because that gives me a 50% roll vs. the 75% roll that I would get if I stood still.

The curve is a parabola since the formula for average experience ends up with a n^2 term in it.

As far a being useful... Notta, zip, zilch I could give a crap what the numbers are when I'm being fired at!! and you can bet your bottom dollar I'm going to use every trick in the book to get my skill% as close to 98% as I can! Only thing it could be useful for is maybe to game balance xp, but they already seem balanced. I was just curious:)

widowmaker wrote:Wait... the minimum XP for a successful check is 15? Does this translate directly to the "XPs earned" portion of the F2 screen? I was watching my XPs in a fight the other night. I had an enemy Titan down in the same hex as mine and shot it with 5 MGs. Each had a 98%, and each hit earned me 2 XP (combat XP, obviously). Are there other factors to XPs earned?

Notice that for attack skill checks (hitting with weapons), the XP earned is divided by 7/10/14 depending on weapon class (heavy/medium/light). This will all be in the updated guide, which will be released after the patch is out.