Quote from: MatteoN;733775AND there would be nothing "counterintuitive" in roll+modifier under skill.

The first edition of the first game I played, Das Schwarze Auge, did just that: you succeeded if your rating was at least as high as a "competing number" that you generated by rolling a d20, sometimes modifying the result if the action was harder or easier than the norm. TSR's Alternity did the same thing using step dice to modify the roll of a d20. This approach imho is better than that traditionally used by BRP etc. because you never have to recalculate your ratings during play. In the end, however, these systems are all equivalent.

90 times of 100 "counterintuitive" to my ears sounds as "my belly-button is the centre of the world".

Yup.

Take the whole 'subtraction is harder than addition' thing.

This gets cited constantly as if it's simply established fact, but there is virtually zero evidence that this is actually the case.

The REAL issue is that THEY find it harder, probably because what the evidence does show is that whatever you're taught first is slightly easier, and most American curriculum starts kids out learning addition first.

But even that's not universal. I've never found it any harder than anything else. You wanna make an argument that long division is harder, I'll probably consider it. Otherwise, all rattling off that detail tells me is what the arguer finds easier, and is trying to appeal to some imagined universal principle to bolster his argument.

Quote from: ForumScavenger;732919Nathan, my opinion on the topic is clear from my posts. Someone asked why people don't like %dice mechanics. I am explaining it.

But, you are not explaining that, you are explaining why people dislike low-level characters.

Most D100 games have a Previous Experience generation that allows you to generate a PC that is at various levels, from beginner to veteran or hero.

I have played a First Level Magic User in D&D with 4 Hit Points and a Magic Missile and Spiderclimb spell. He was absolutely useless, except when climbing around. Fortunately, the first scenario was based on a ship, so he could climb around the rigging for a while, but put him in combat and he could fire one shot and maybe hurt a goblin, or could fight and almost certainly die.

So, low level characters is not a D100 problem, at all.

Quote from: JeremyR;733777Buck Rogers used a roll under d100% system, but it did difficulty by multiplication.

Easy 2x
Average 1x
Difficult 1/2
Impossible 1/4

That would probably make people's minds explode today. Multiply by a fraction?

If only there were a simpler way of expressing that - divide by four, for example.

(Or buy a cheap calculator from the pound shop, and put it on the table during games.)

Quote from: gamerGoyf;733668Honestly it's not hard to see why roll under % would be "disdained mechanic" in certain circles. While it seems that since %'s are the way most people in the first world think of probability such systems would be elegant and easy to grok, but that really hasn't been the case historically.

Quote from: gamerGoyf;733668RPGs (except the super abstract ones) care about how good you are and how hard the task is, and representing that is super awkward in a roll under % system.

I wonder if you have actually played with a D100 system.

This is exactly what D100 systems are very good at.

How good you are is represented by the skill - low skill means you are not very good at the job, high skill means you are good at the job.

How hard the task is can be represented by a modifier to the skill, either as a multiplier/divisor or by adding/subtracting a bonus/penalty. The bigger the penalty, the harder the task.

Quote from: deadDMwalking;733732gG is basically right.   First issue, if you say +10%, is that making it easier or harder?  Could be either.  If you add it to your skill modifier, it makes you better.  If you add it to your roll, it makes you worse.  If you write -20% to things that make you better at your task because you apply it to the die roll, it's counter intuitive...  Your chance is increasing but it's written as a negative.

Are you just trying to be very theoretical here? You are trying to say that using the same terminology for roll-under and roll-over systems is confusing.

Sure, if I used a Rolemaster mechanic in BRP/RQ then it would be confusing and vice versa.

However, all D100 games state how the skills are used.

In RQ/BRP/Legend/OpenQuest-style games, having a +20% bonus to a skill increases the change of succeeding by 20, and having a -20% pena,lty means subtract 20 from your skill. Purists may say that +20% might mean "Add on fifth of the skill", but the convention means something different.

Quote from: deadDMwalking;733732If you apply everything to your skill (so bonuses are written as positives and penalties are written as negatives), then you have to potentially apply positives and negatives at the same time (for difficult tasks with circumstantial bonuses), so you're potentially refiguring your skill each time.  

That is exactly how many D100 skills work.

Quote from: deadDMwalking;733732All of these issues are relatively minor, but taken together, they detract from the mechanic.

And to me they enhance the mechanic.

Quote from: deadDMwalking;733732Finally, most d100 systems use increments of 5%, so they don't take advantage of the one advantage of a day - more granular results.

Since 1985, most D100 systems have used a scale of 1% increments. I am sure that if we listed out all the D100 games then that would be the case.

Quote from: soltakss;733788I wonder if you have actually played with a D100 system.

This is exactly what D100 systems are very good at.

How good you are is represented by the skill - low skill means you are not very good at the job, high skill means you are good at the job.

How hard the task is can be represented by a modifier to the skill, either as a multiplier/divisor or by adding/subtracting a bonus/penalty. The bigger the penalty, the harder the task.

UM.  yes to this.  +1.

It's a sad day when gamers raised on d20 can't grasp roll-under.

Quote from: The Butcher;733809It's a sad day when gamers raised on d20 can't grasp roll-under.

My eyes are bleeding reading this thread.

Quote from: J Arcane;733784But even that's not universal. I've never found it any harder than anything else. You wanna make an argument that long division is harder, I'll probably consider it. Otherwise, all rattling off that detail tells me is what the arguer finds easier, and is trying to appeal to some imagined universal principle to bolster his argument.

Yeah.  I play with a bunch of folks who can calculate THAC0 faster than they can look it up on a table.

Me, when I try to make even a simple calculation, I go "uhhhh..." and there's about a five second delay while I activate my brain's arithmetic processing unit.  In that amount of time I can look something up on a table so it's faster than me.

Most people don't appear to have that brief delay while their brain-meats switch to arithmetic mode.

When someone says 'this way is harder', it doesn't mean 'it's too hard for me and I need to go back to first grade!'.  

If you roll a die, you have a variable.  Variable plus modifiers is easier for most people than variable compared to fixed value modified by variable values.

d100 against TN of (skill +/- modifiers) means you have variables on both sides of the equations.  

How much harder is that?  It depends on the person.  

When designing our homebrew, we frequently invoke the 'Mary Principle'.  One of the main designers is involved in advanced math for his career; two of us are pretty decent with numbers.  I, personally, am really good at adding double-digit numbers together (17+35, for instance).  Mary has trouble with that.  It takes her longer than it takes me.  If we have too many operations, she really struggles.  She's not the only one, but she usually struggles the most.  

When we're designing a system, we don't design it based on what functions we can do.  We try to design for the 'lowest common denominator' - people who aren't good at math.  

I don't think that 'good at math' needs to be a requirement in order to enjoy roleplaying games.  Considering how much more I value imaginative play than number-crunching, I think focusing on making the math easy and intuitive is time well-spent.  

I certainly don't spend time deriding folks who really do struggle with the math.  I know lots of intelligent people that suffer from 'innumeracy'.  

If someone uses more complicated math when less complicated math is available, they ought to have a compelling reason regarding flavor reasons.  But that doesn't mean I advocate everything on a d20+modifiers.

For example, in Deatwatch (roll under), I suggest adding your skill to your d100 roll against a fixed target of 100.  I suggest applying 'circumstantial modifiers' to the die roll, rather than the TN.  I like to keep all operations on one side of the equation; most people intuitively grok that better.

Quote from: deadDMwalking;733820When someone says 'this way is harder', it doesn't mean 'it's too hard for me and I need to go back to first grade!'.  
.

He didn't say, "this way is harder."  He said, "this way is super awkward."  That's a pretty significant difference.  The second clearly implies that he has difficulty figuring it out.  

And you agreed with it, so you can't blame people for making the comments they have made.

@ deadDMwalking: I think you're forgetting that in "roll and add" systems the target number too is a variable, so variables are on both sides of the equation both in "roll under" and in "roll and add" systems. It couldn't be otherwise, since the systems are functionally equivalent.

If you want a system with very easy maths, try roll under with step dice: roll under skill (rated 1 to 5) with a d6, d8, d10, d12 etc. depending on the difficulty. All maths required is comparison of result with rating and of result with result (highest under skill wins).

Quote from: Benoist;733813My eyes are bleeding reading this thread.

Quote from: JeremyR;733777Buck Rogers used a roll under d100% system, but it did difficulty by multiplication.

Easy 2x
Average 1x
Difficult 1/2
Impossible 1/4

A common (house) ruling in d100 roll-under games.

Quote from: deadDMwalking;733820d100 against TN of (skill +/- modifiers) means you have variables on both sides of the equations.  

R ≤ S + M

where
R is d100
S is skill
M is modifiers

vs

R + S + M ≥ T

Where

R is any dice roll you like
S is skill
M is modifiers
T is target number

In both approaches you take your skill (a number off your character sheet) and then you apply situational modifiers (numbers from the rules or GM/Player judgments about the situation) and then you either:

1) roll some dice and ask "is it equal to or less?"

2) roll some dice and add it to the total and then ask "is it equal to or more?" to the target (another number supplied by the rules or the GM).

Quote from: MatteoN;733824If you want a system with very easy maths, try roll under with step dice: roll under skill (rated 1 to 5) with a d6, d8, d10, d12 etc. depending on the difficulty. All maths required is comparison of result with rating and of result with result (highest under skill wins).

Tales from the Floating Vagabond had a pretty sweet system.  Is there a game with a serious take using it?