# New Difficulty Calculations

I can safely assume this new trait on our qualities will be explained, but it appears to expand the range at which you can apply difficulty checks.
For Narrow, the # appears to denote the percentage of 100% that gets applied when you have a point above or below the difficulty check.
For Broad, well, haven’t figured it out yet…

Narrow 10 (100/10 = 10%); Skill @ 6, Difficulty 6 = 50% Chance
Narrow 10 (100/10 = 10%); Skill @ 6, Difficulty 7 = 50-10 = 40% Chance
Narrow 9 (100/9 = ~11%); Skill @ 6, Difficulty 7 = 50-11 = 39% Chance
Narrow 5 (100/5 = 20%); Skill @ 6, Difficulty 7 = 50-20 = 30% Chance
Narrow 4 (100/4 = 25%); Skill @ 6, Difficulty 7 = 50-25 = 25% Chance

However at 3, it starts to go awry…
Narrow 3 (100/3 = 33%); Skill @ 6, Difficulty 7 = 50-33 = 17, but you have a 33% Chance instead…
Narrow 2 (100/2 = 50%); Skill @ 6; Difficulty 7 = 50-50 = 0, but you have a 50% Chance instead… (Shouldn’t you have 10%?)
Narrow 1 however seems to be a guaranteed 100% Chance

Also, it appears that the defaults for our qualities were set to Broad 10 (They probably should have been set to Narrow 10!).

I had been play testing and wondered all of a sudden why I had an 8% chance of success, when my Skill is at 6 and the Difficulty check was only 7!
edited by Zebulan on 1/31/2013

So it appears that I was just online at the worst time, as the Reference Guide has since been updated providing the new calculations.

[quote=]For Broad difficulties, the chance of success is:
QualityLevel / DifficultyLevel * (DifficultyScaler%)
with a minimum 1% chance of success. (The default DifficultyScaler is 60%.)

For Narrow difficulties, the chance of success is:
50% + ((QualityLevel- DifficultyLevel) * (DifficultyScaler%))
with a minimum 10% chance of success. (The default DifficultyScaler is 10%.)[/quote]

If anyone is interested, I threw together an excel calculator (Excel 2010) which can help with the calculations to visually see the impacts your qualities, difficulties and scale values will have. Just edit the yellow square and voila, all done.

And it’s made me spot something in the manual which doesn’t quite add up:

“for Narrow difficulties, a character has a 50% chance of success if their quality is equal to the difficulty level. If their quality is four points or more lower, it’ll be a 10% chance of success; four points or more higher, and it’ll be a 100% chance of success.”

Both my counting-on-fingers, and your spreadsheet, suggest that the final bit of this should be “five points or more higher”.

Perhaps someone from FBG could confirm that?

(The reason for asking: I’d always assumed that there was a chance of failing a Straightforward challenge no matter how Straightforward it actually was. So there’s an alternative possibility, which is that it ought to say “four points or higher, 90% chance of success”.)

Cheers
Richard

[quote=Richard ]And it’s made me spot something in the manual which doesn’t quite add up:

“for Narrow difficulties, a character has a 50% chance of success if their quality is equal to the difficulty level. If their quality is four points or more lower, it’ll be a 10% chance of success; four points or more higher, and it’ll be a 100% chance of success.”[/quote]

I never noticed that, but I also think the statement as a whole has lost its relevance. Since now you can have a difficulty scale; the statement assumes that it’s Narrow 10 (default). If it’s Narrow 5, well, now it’s 8 points lower for 10% and 10 points higher for 100%.

Ultimately though, that is a valid point… Either it’s a 90% cap at four points higher (Narrow 10, specifically), or 100% at five points higher. I would lean towards typo and it should be five points, rather than lean towards “they forgot to tell us about the 90% cap.” Haha.

Sorry, I have done FBG an injustice by trimming the quote excessively. It does say “with the default DifficultyScalers”.

It’s trying to simplify things back down for people who don’t want to be bothered with Proper Mathematics.

Cheers
Richard

[color=#009900]Yes, it was a typo. Sorry about that.[/color]