Skill Challenges: Is "harder" really harder?

[thc1967]

This has sort of been bugging me since I read the excerpt on skill challenges. Maybe I'm misunderstanding it. Fair warning: rambling ahead...

Skill challenges are set up so you need X successes before Y failures. The X and Y seems to always be set up in a 2:1 ratio, such as 4/2, 6/3, 8/4, etc.

The thing is, they're calling 8/4 "harder" than 4/2. But I don't see how that can be the case given the same DC for both. Both have the same ratios, so mathematically they are both the same degree of difficulty. One just takes longer than the other to resolve.

It would seem, again given identical DC, that one would control the difficulty of the encounter by the ratio of successes to failures rather than the sheer number of successes or failures possible. For example, 4/1 is a whole heck of a lot harder than 4/3, because with 4/1 your first failure loses you the encounter whereas with 4/3 you get a couple more chances.

Thoughts?

 

[Cirex]

I understand your point, and I'm thinking about limitations on skill use:

1) Skills usable in a skill challenge template -> Athletics doesn't make much sense in the "diplomacy" template.

2) How many times can you use a determinate skill? Can you have success in a skill challenge by just rolling diplomacy? If this was not the case, 8/4 becomes harder, since the amount of usable and trained skills to reach those 8 success with a good success chance is harder overall.
Let's say you can just use each skill once and you got to discuss something with the King. Diplomacy, bluff, intimidate, nature, arcana, religion and any other random one are the main skills. With a party of 4, it may be hard to get 8 success with just trained skills. While if it was 4/2, it would certainly be easier. However, I have no clue how many times you can use a certain skill, if it's limited at all.

3) Automatic fails on some skills (intimidate from that excerpt, in example) and the issues arisen with my second point.

 

[Serensius]

They're actually not saying 'harder', they use 'more complex', as in, takes longer to finish. Also, a 4/1 challenge is basically pointless, because if the PCs fail the first check, it'll be over before they even knew what hit them. I think it's okay this way; decide complexity based on the scope of the challenge (a lengthy encounter with the obstinate count versus saving a boy trapped under a fallen tree), and DC based on the difficulty and level of the PCs. And of course, there's nothing that says you can't modify the success/failure ratio.

 

[UngeheuerLich]

This has sort of been bugging me since I read the excerpt on skill challenges. Maybe I'm misunderstanding it. Fair warning: rambling ahead...

Skill challenges are set up so you need X successes before Y failures. The X and Y seems to always be set up in a 2:1 ratio, such as 4/2, 6/3, 8/4, etc.

The thing is, they're calling 8/4 "harder" than 4/2. But I don't see how that can be the case given the same DC for both. Both have the same ratios, so mathematically they are both the same degree of difficulty. One just takes longer than the other to resolve.

It would seem, again given identical DC, that one would control the difficulty of the encounter by the ratio of successes to failures rather than the sheer number of successes or failures possible. For example, 4/1 is a whole heck of a lot harder than 4/3, because with 4/1 your first failure loses you the encounter whereas with 4/3 you get a couple more chances.

Thoughts?

Its not difficulty, its complexity which means a complex thing needs more than just 3 secs to resolve (Thievery against traps)

 

[Cadfan]

1. I don't think they mean "difficulty" the same way you do. I think they mean it in the sense that performing a difficult task for 2 minutes is harder than performing it for 1 minute, even if the tasks are equally hard per second.

2. Actually, I'm pretty certain that the math doesn't work the way you think, due to regression to the mean as the number of trials increases.

3. I don't think the regression to the mean issue matters, because the real difficulty comes from the skills and the interaction between the DM and the players. Coming up with 8 useful things to do to save the people of a town from a fire is harder than coming up with 4. The die roll odds are a secondary source of difficulty, not the primary.

 

[salsb]

This has sort of been bugging me since I read the excerpt on skill challenges. Maybe I'm misunderstanding it. Fair warning: rambling ahead...

Skill challenges are set up so you need X successes before Y failures. The X and Y seems to always be set up in a 2:1 ratio, such as 4/2, 6/3, 8/4, etc.

The thing is, they're calling 8/4 "harder" than 4/2. But I don't see how that can be the case given the same DC for both. Both have the same ratios, so mathematically they are both the same degree of difficulty. One just takes longer than the other to resolve.


Thoughts?

Yeah, your analysis isn't correct.
The probability of getting 8 successes before 4 failures is worse than the probability of getting 4 successes before 2 failures.
To figure this out, you find the probability (from the negative binomial distribution) of having 8 successes and 4 failures, plus the probability of having 8 successes and 3 failures, plus having 8 successes and 2 failures, and so on, and similiarly for 4 successes and 2 failures.
For example (using Neo Office's NEGBINOMDIST function), if you have a 50% chance of success, then 8/4 gives you a 19% chance of success, and 4/2 gives you a 34% chance of success.

 

[Lacyon]

The thing is, they're calling 8/4 "harder" than 4/2. But I don't see how that can be the case given the same DC for both. Both have the same ratios, so mathematically they are both the same degree of difficulty. One just takes longer than the other to resolve.

As mentioned by so many others before me, 8/4 is more "complex" than 4/2, not "harder".

As for the math, the probabilities are identical so long as each check has (about) a 13/20 probability of being a success (giving the party about a 43% chance of succeeding at the challenge itself).

When the chance of each individual check passing gets smaller, a less "complex" task is easier than a more "complex" task - you only have to get lucky a few times to squeak out a victory. The Law of Averages is against you, but it has less influence the fewer dice you roll.

When the chance of each individual check passing is higher, the more "complex" tasks is easier than the less "complex" task (though both become very likely to succeed fairly quickly). The Law of Averages is now firmly on your side, so rolling more dice is to your benefit.

In actual gameplay, the likelihood of each individual action yielding a success will vary from character to character, so the exact probability of party success is difficult to calculate. But the main mechanism for increasing the difficulty of a task is the DC of the individual checks, rather than the complexity of the task itself.

 

[Kraydak]

...
In actual gameplay, the likelihood of each individual action yielding a success will vary from character to character, so the exact probability of party success is difficult to calculate. But the main mechanism for increasing the difficulty of a task is the DC of the individual checks, rather than the complexity of the task itself.

Edit: Bleh, stupid difference between fail/success/success being failure or a success. I should have know better that post before coffee after "accidentally" starting a Civ game at 11:45 last night.

 

[Lacyon]

Well, the difference between a 2/1 and an 8/4 at 50% success/roll is a factor of 2 (37.5% vs 19.4% total success rate). I'd say the complexity is a significant (if non-trivial) factor in the overall difficulty.

I wouldn't expect that 50% success/roll is an average the designers are shooting for.

EDIT: Actually, the success rate on a 2/1 roll is only 25%. This would be a "complexity 0" skill challenge. The success rate on "complexity 2" skill challenges is about 14.5%. I think you've failed to account for the fact that the total number of rolls is (at most) one less than the sum of the maximum successes and maximum failures.

Regardless, if the DC on this challenge were reduced by 3, the difficulty would remain (approximately) the same across complexities. If it were reduced by more than 3, more "complex" skill challenges actually become easier. This means that adjusting the complexity has an inconsistent effect on actual challenge difficulty.

If you want to make something harder or easier, and don't have your PCs character sheets handy to punch numbers in a spreadsheet, change the DC instead of the complexity.

 

[salsb]

In actual gameplay, the likelihood of each individual action yielding a success will vary from character to character, so the exact probability of party success is difficult to calculate. But the main mechanism for increasing the difficulty of a task is the DC of the individual checks, rather than the complexity of the task itself.

While this is true, as the DC sets most of the difficulty.

As mentioned by so many others before me, 8/4 is more "complex" than 4/2, not "harder".

This is not true. Requring more successes even while keeping the ratio of successes to failures the same, does make it more difficulty in that a lucky roles are less likely to succeed (since you need more of them). If you have a simple check, and you need a 10 to succeed, the odds are 55%, while for the 8/4 check you only have a 19% chance. That makes it harder for lesser skilled characters to succeed at more complex tasks. Which strikes me as harder.

Though, these complex checks make it harder for skilled characters to fail as well. If you need (for example) a 3 or less to fail, then for a simple check you have a 15% chance to fail, but on the 8/4 check you have only ~7% chance to fail.

Edit: I was thinking up to 4 failures not at most 4 failures.