The negative effect of this change is perhaps that it reduces some of the 'edgeplay' and tension of "I just got enough for that finishing degree".

The positive is that it may reduce one of the game's perhaps major slowdowns: calculating DoS.

As those 'edgeplay' cases were reasonably rare, the impact of the change is likely overall positive-- and of course, GMs who like a bit more calculation can always award successes for closeness.

However, a full d10 system, where there is almost no edge for basic success and perhaps no ability to use +5 alterations would likely be quite dull.

Percentile d100 does have significant advantages as a base over d10, including perhaps the often overlooked 'familiarity' effects.

I can see the argument for +5 modifiers being a good thing, but the thing is, in the system as it stands, they're not used enough to be considered remotely relevant (in my opinion, anyway).

Basically there's two options here. Strip things down to a d10 like the system clearly so wants to do, or make the ones digit actually relevant to play.

I can see the argument for +5 modifiers being a good thing, but the thing is, in the system as it stands, they're not used enough to be considered remotely relevant (in my opinion, anyway).

Basically there's two options here. Strip things down to a d10 like the system clearly so wants to do, or make the ones digit actually relevant to play.

The ones digit is highly relevant. The effects are simply often overlooked because most people don't analyze the game dynamics:

1. Basic Success versus Basic Failure is one of the most common game decisions. The edge between those two that the ones digit forms creates a significant portion of the game's tension.

2. Explicitly rendered percentages out of 100 tend to be easier for humans to read in probabilistic assessments.

3. Narrative implications may heavily be based off the ones digit, as at a glance players and GMs may treat a 30 strength quite differently from a 38 strength.

There are perhaps others, but those may be a reasonable start.

FFG may certainly still have significant design space open to do creative things with the ones digit yet, though. Hit locations and Perils might only be the beginning.

I can see the argument for +5 modifiers being a good thing, but the thing is, in the system as it stands, they're not used enough to be considered remotely relevant (in my opinion, anyway).

Basically there's two options here. Strip things down to a d10 like the system clearly so wants to do, or make the ones digit actually relevant to play.

The ones digit is highly relevant. The effects are simply often overlooked because most people don't analyze the game dynamics:

1. Basic Success versus Basic Failure is one of the most common game decisions. The edge between those two that the ones digit forms creates a significant portion of the game's tension.

2. Explicitly rendered percentages out of 100 tend to be easier for humans to read in probabilistic assessments.

3. Narrative implications may heavily be based off the ones digit, as at a glance players and GMs may treat a 30 strength quite differently from a 38 strength.

There are perhaps others, but those may be a reasonable start.

FFG may certainly still have significant design space open to do creative things with the ones digit yet, though. Hit locations and Perils might only be the beginning.

I want to address some of these assertions

1) I've already pointed out that the one's digit is only coming into play 10% of the time (although it technically comes up more often if you only count successful rolls: a BS in the 30s will use the 1s digit 25% of the time for successful rolls). I don't think that's actually providing tension in a consistent enough manner. This and all of the other arguments about the d100 don't hold a lot of water to me. The tension I get from rolling a d100 is usually closer to "I have an equal chance to roll a catastrophic failure as I do to roll a single successful number" in combination with "wow, my character is more likely than not to fail and have nothing interesting occur!" There are ways to address the latter within the d100 system, but why bother keeping it on?

2) Here's the issue with that. You has an equal chance of rolling a 1 as you do a 100. The d100 is swingy. Incredibly swingy, because there are 100 different outcomes that are all equally likely to occur on a roll. Yes, you can look at the dice and say to yourself that you have a 52% chance of success. Okay. That isn't really adding anything to theme. You also can't really do a lot planning; every time you roll the dice it's in the hope of being lucky and not being unlucky. The die is so swingy that you can't really assume anything with it and are left flailing when it comes up poorly. This is a flaw with every system that uses a single die. If you bring In multiple dice, creating a bell curve, you can suddenly say that you know the dice will frequently roll somewhere in the middle. It becomes easier to plan math around this. You lose the inherent knowledge of percent chance, but, BUT I would argue that knowing your percent chance of success has **** all to do with actually engaging in the story and more to do with playing a numbers game. It adds no narrative weight. With a bell curve, you roll the dice knowing that most of the time you'll get average results but sometimes things can go awry.

3) I haven't seen a whole lot of narrative implications arising from the 1s digit, personally. The game is designed around characteristic bonuses, and those are what the rules use to differentiate characters. You have a maximum of 9 points out of 100 to do this differentiation with. The difference between a person at 30 and 39 strength is essentially a below averse and an above average person, though neither remarkably so. Does that really matter that much? Can't you just describe them that way rather than ascribe a number. The mechanical difference between them is neglible, given how rarely that one's digit comes up. If you're expecting to be able to describe every minute difference between character mechanically (and this is a minute difference), you're looking at a much more complicated system.

I want to address some of these assertions

All of your points seem to be purely opinion, to be honest.

You should simply look up human psychological studies on data comprehension starting with "just noticeable differences" into "familiarity heuristics", and then to advertising implementations and object permanence.

Suffice it to say that 9.99 is perceived very differently from 10, and something like 25% is more than enough to form a point of emotional activation. (Perhaps examine "natural 20" in Dungeons and Dragons, which may obviously occur 5% of the time.)

In essence, the "close but no cigar" effect is highly prevalent on Basic Success decisions.

Yes, the mathematical proof that the ones digit only matters 10% of the time is "purely an opinion".

Where's the roll-eyes smiley?

Yes, the mathematical proof that the ones digit only matters 10% of the time is "purely an opinion".

Where's the roll-eyes smiley?

You obviously didn't read the discussion in your attempt to sound snarky.

The effects of this "mathematical proof" on the totality of the game are perhaps in question.

I want to address some of these assertions

All of your points seem to be purely opinion, to be honest.

You should simply look up human psychological studies on data comprehension starting with "just noticeable differences" into "familiarity heuristics", and then to advertising implementations and object permanence.

Suffice it to say that 9.99 is perceived very differently from 10, and something like 25% is more than enough to form a point of emotional activation. (Perhaps examine "natural 20" in Dungeons and Dragons, which may obviously occur 5% of the time.)

In essence, the "close but no cigar" effect is highly prevalent on Basic Success decisions.

I have no idea what part of what I said you are rebutting. I am aware about the psychological importance of numbers and how they're interpreted, but that isn't a valid argument for the d100 system. I've already brought up that the ones digit actually comes I to play 10% of the time. One roll out of 10. That's maybe twice a game. It's actual effect on the mechanics of the game is negligible.

So what about the psychological impact of having a d100? I would like you to present me with a study showing that people find significantly more enjoyment or attachment or narrative impact from rating skills from 1 to 100 rather than 1 to 10. And no, I don't want a study looking at advertising, because this is a game. If you're going to cite psychological science, you have to be **** careful to not overgeneralize findings. I could present studies to you on scale development that show diminishing returns on having rating scales longer than, say, 10 points, but that wouldn't necessarily be applicable, would it?

And the "close but no cigar" effect in my experience just leads to frustration and temptation to stretch the rules rather than any kind of achievement. You have to keep the goals of the game mind, here. The goal of your game should not be for the player to fail and have nothing happen, it should be for the players to always be doing and reacting to interesting things. That 0-9 are not making interesting things happen. You aren't getting enough rolls in the game for "close but no cigar" to be balanced by actual success, and you typically aren't rolling for things you get repeat attempts at.

As far as differentiating characters go, I would ask you to tell me what is significantly different about a creature with 63 strength and one with 68 strength. That extra descriptive utility is lost, in my opinion, once you get out of the "human average" range of 20-50. So now you have that descriptive utility only applying 30% of the time. It doesn't justify itself.

I have no idea what part of what I said you are rebutting. I am aware about the psychological importance of numbers and how they're interpreted, but that isn't a valid argument for the d100 system. I've already brought up that the ones digit actually comes I to play 10% of the time. One roll out of 10. That's maybe twice a game. It's actual effect on the mechanics of the game is negligible.

The effect happens to be modeled by a gaussian distribution, and occurs roughly 3% of the time around the skill target.

The emotional activation tends to occur when the dice number misses by one, hits exactly, or passes by one.

My post actually mentioned at least four things for you to simply google on that and perhaps the other topics, but as you seem to have zero familiarity with game theory and the psychology of data processing or rewards, posting to you links on basic textbooks seems pointless.

And no, I don't want a study looking at advertising, because this is a game.

It's a completely inane contention to state that the effects involved are unrelated. You think gambling, gaming, and advertising have no psychological connection?

That alone likely makes further discussion rather inconsequential.

Ah yes, the old "I'm called on my bull and obfuscate backing it up by saying that it's too complicated to understand." What a great argument you made!

How are you getting a normal distribution (this is what a Gaussian distribution is if you're writing for a more lay audience) off of the rolls from a single die (which always have a flat distribution).

If you're going to cite "just noticeable differences", give me a study in which they're used on game characteristics. This is what we're arguing, yes? That the d100 system still has noticeable differences between characters? I said that its apparent in the human average range, but you failed to address my point about anything above 50.

And are you saying the familiarity heuristic is an argument for the percentile system? Hm, I'd better tell the best selling games in the world and the most played ones to throw away their 6-sided dice because they don't give you easy probabilities! I suspect you're misusing this term.

I already brought up that advertising is not an acceptable translation to playing games. I'm sorry that you disagree with proper research practices.

Object permanence is a stage in development In which a person can understand that something exist even if it is not in their immediate perception. What does this have to do with dice?

Continue to pretend that using technical terms makes you an expert above reproach, though, and feel free to tell me how I totally just am not capable of understanding your high-level theories that you offer no explanation for. Here's a hint: you're not actually good at something unless you have the capability to explain it, barring having some type of social disorder.

Object permanence is a stage in development In which a person can understand that something exist even if it is not in their immediate perception. What does this have to do with dice?

If you were more familiar with it, you'd realize that it includes persistent probabilistic effects. Something with the chance to occur in the future.

Are you aware of adrenal effects in gambling? The effect of one win on losing streaks, yes?

If you're going to cite "just noticeable differences", give me a study in which they're used on game characteristics.

How about you produce a study indicating the human psychological principle isn't applicable to games?

Will you demand a study that specifically states gravity relates to dice RPGs?

And are you saying the familiarity heuristic is an argument for the percentile system? Hm, I'd better tell the best selling games in the world and the most played ones to throw away their 6-sided dice because they don't give you easy probabilities!

It is obviously and undeniably a point in favor of percentiles. That point in favor of percentiles by no means completely invalidates other gaming systems, as I believe your "straw man" hyperbole is meant to propose.

How are you getting a normal distribution (this is what a Gaussian distribution is if you're writing for a more lay audience) off of the rolls from a single die (which always have a flat distribution).

Because the emotional effect is vastly pronounced at the target, highly pronounced at one off the target, and much less pronounced at two off the target, though still relevant.

All of this is honestly: you should just start with B.F. Skinner, and maybe move on to John B. Watson. That's probably where the basics start.

In essence, you're trying to argue that a pure mathematical probability is in vacuo all that matters to an roleplaying game, and that human psychology is irrelevant.

That's basically almost always going to be wrong. The straw man of "it's only 10%" is just that. The 10% is pretty much only useful with context.

Some nonsense.

Christ. And you people think I'm a smug *******.

TI how about instead of name dropping Wikipedia articles you lay out for us obviously intellectually inferior plebes how any of this applies to game design, and more importantly, how these things tell us we should build the Dark Heresy 2 system to work.

When would a gun jam? A WS test result of 10? When would a reliable gun jam? 10 again? Would this mean drastically reducing the special qualities of weapons, or completely reworking and rewriting them? What about opposed Tests, how would they be resolved, especially in the event of a tie? Wouldn't it be better to use multiple d10 than just one? Would this mean a complete rewrite of the whole game, or would the vaunted backward compatibility to previous lines again take precedence?

I am aware that there are psychological factors involved with rolling dice. You are also attempting to shoehorn them into an argument for the d100.

Persistent probabilistic effects are going to be available for any kind dice you roll. This is not inherent to the d100. Same goes for adrenal effects on gambling. Also, I already brought up that gambling is not an appropriate analogue to RPGs due to the varying meanings of the dice rolls and the lack of structure for when they will take place next. Related, sure, but not enough to directly translate the theories without research.

Actually, I don't have to produce that study because it's the null hypothesis that all science is based on. YOU need to produce a study that allows you to reject that null. And, if you are unaware of how a null hypothesis works, it is the baseline assumption that phenomena are not related that all psychological science works off of. You do a study in order to reject that null by showing a relationship. And gravity has a law behind it, unlike psychological science. Nice straw man yourself.

Your point about familiarity being in favor of d100s could easily be used to say we should just switch to d6s, since they're more familiar. I'd imagine that if you told people to choose between rolling a d6, rolling, a d10, and rolling 2d10 and using one as the 10s digit with the zero differing in value based on whether you roll two of the or if just the tens digit is a zero would probably be least familiar with the d100.

I can see now where you're getting a normal distribution from, although I don't quite think it would qualify due to the effects not being equal in BOTH directions from the center point. Maybe there's a Gaussian distribution that describes this, though. Regardless, I don't see you showing any proof that this effect is greater on the d100 than the d10. Do you have a study showing that the larger the range of possibilities, the stronger the effect? I'd accept that, and it would seem to be intuitively true. Regardless, though, I don't think that it's a firm enough argument in the d100s favor given humanity's overwhelming preference for d6s.

When would a gun jam? A WS test result of 10? When would a reliable gun jam? 10 again? Would this mean drastically reducing the special qualities of weapons, or completely reworking and rewriting them? What about opposed Tests, how would they be resolved, especially in the event of a tie? Wouldn't it be better to use multiple d10 than just one? Would this mean a complete rewrite of the whole game, or would the vaunted backward compatibility to previous lines again take precedence?

Oh my god thank you for making a coherent post. Yes, all of those things would need to be worked out, and downscaling to d10 would definitely kill compatibility. I think you could tie jamming to degrees of failure/how badly you missed the roll by, though.

Christ. And you people think I'm a smug *******.

TI how about instead of name dropping Wikipedia articles you lay out for us obviously intellectually inferior plebes how any of this applies to game design, and more importantly, how these things tell us we should build the Dark Heresy 2 system to work.

Well when someone arrogantly demands studies on extremely basic 'Wikipedia' things...

As for DH2, I did mention how these apply:

Since the amount of times the player just gets a single critical degree more for an effect is vastly less than the amount of times the player gets very close to or just over a basic success--

The change to minimize the calculations of DoS while preserving the 'edge play' of basic successes was likely sound.

Those "I just passed" effects are highly pronounced moments in the game, when they do happen, and so should be preserved. (Rather than a full d10 system.)

Given the other benefits I listed for d100, I'd likely recommend looking at making the ones digit more mechanically interactive, instead of removing it. (Although they make a reasonable show of this in hit locations and diverse Perils of the Warp tables, which again may add tons of flavor to the game.)

Persistent probabilistic effects are going to be available for any kind dice you roll. This is not inherent to the d100. Same goes for adrenal effects on gambling.

No, no. One of the effects in question was the roughly 3% occurrence around a skill target. To wit: " Just failed by one, passed exactly, and just passed by one. "

Can you see how that might be different on dice with less numbers? Can you see the emotional effect involved?

Actually, I don't have to produce that study because it's the null hypothesis that all science is based on.

If a study says that gravity affects all matter, and a another study states that dice are made of matter, a third study stating that gravity affects dice is not implicitly required.

So yes, you do have to produce a study if you're claiming indicated human psychological effects are somehow unrelated to RPGs.

I mean you obviously are just trying to flail the burden of proof around with zero experience in the field.

Bottom Line: You claimed that a 10% chance of effect had a negligible enough effect upon the game that it could be discarded.

You provided no proof of that.

For someone who likes to frivolously demand specific studies, you certainly like to compose your personal arguments with:

" I don't think that's actually providing tension in a consistent enough manner. "

Can you give us the peer reviewed journal which backs that up?

So, how about you actually read up on the indicated psychological effects, because there are certainly more than a few studies on them.

When would a gun jam? A WS test result of 10? When would a reliable gun jam? 10 again? Would this mean drastically reducing the special qualities of weapons, or completely reworking and rewriting them? What about opposed Tests, how would they be resolved, especially in the event of a tie? Wouldn't it be better to use multiple d10 than just one? Would this mean a complete rewrite of the whole game, or would the vaunted backward compatibility to previous lines again take precedence?

Oh my god thank you for making a coherent post. Yes, all of those things would need to be worked out, and downscaling to d10 would definitely kill compatibility. I think you could tie jamming to degrees of failure/how badly you missed the roll by, though.

If you roll a 0 (10) to hit roll a d10. If the result is above your (B|W)S bonus, the gun jams.

TI I don't really understand what you wrote in response to me, but the last bit seemed related to game design, so for my next question: How do you think the ones digit of a characteristic score could be made more relevant? What changes would you make to make that number matter more than 10% of the time?

It's your opinion that the d100 gives a stronger effect than a d10. Show me a study of it. Why am I asking you to show a study? Because you're the one who started throwing around academic terms and pretending to be the smartest person in the room. Well, that's fine, but you don't get to throw around things like that in academia that don't have studies behind them while trying to act like the study is authoritative. I said I was willing to accept you showing a study that larger ranges produce larger effects would apply to the d100. Surely a study like that exists for you to find?

And I didn't bring up proof of me saying the 10% is inconsequential because no one in the thread was expecting academic rigor until you decided to try dropping technical terms with no explanation of them in the hopes that other people would do your work explaining them for you. That's being intellectually lazy.

And no, I don't have to produce a study saying that those effects aren't related to RPGs. As I said, psychological science works by disproving a null. If you write an academic paper stating that the arousal caused by driving cars can be directly ported over to that caused by driving motorcycles, you're going to be told to back that up. That is something for the Directions for Future Research part of the paper, not the Results.

And I said "think" specifically to pull out the fact that it was opinion. I've given solid mathematical reasons for the d100 not being that great, and the only rebuttal you've given is that it causes a greater reaction to close rolls (which if you'd just said that, I'd take it at face value, but if you're going to cite academic work I expect you to back it up), which again only happens a small percent of the time and it's debatable if that small amount of time is worth the including it.

So yeah, you're the one who smugly came in here with a holier than thou attitude. Back that **** up or lose the attitude.

How do you think the ones digit of a characteristic score could be made more relevant? What changes would you make to make that number matter more than 10% of the time?

Well first, somewhat of a fallacy should be addressed:

In the game of Dark Heresy, the ones digit is used for more than determining degrees on a skill test.

This equates to its effect occurring more than the touted '10% of the time'.

Location of weapon hit on target is determined with the ones digit, most of the tables in the game (like Perils of the Warp) take advantage of the expanded ability to list items.

All of those abilities would be lost in a pure d10 system.

So then, you want it to matter more for skill resolution?

One method is of course what is largely done with psykers: "If you roll a nine, you explode."

"If you roll doubles, something good/bad/neutral happens." is another potential.

Making a game enjoyable involves having mechanics that while detailed, are easy to pick up. Sacrificing detail for ease is not always the best.

Although unfortunately FFG isn't paying my salary, so exhaustively listing all you could do with the ones digit probably isn't best. But hopefully you can see at least part of the usefulness of it.

It's your opinion that the d100 gives a stronger effect than a d10.

No, it's perhaps as you might say 'mathematically proven'-- success and failure on a d100 are probablistically closer. You can miss or hit by about 1%, rather than likely 10%.

As for whether hitting by 1% tends to be more emotionally activating than by 10%, I can perhaps only indicate a more detailed examination of the relevant material.

See the stuff you brought up to CPS were legitimate uses of the d100. That was a decent post, if still partly wrong. Rolling d100 for random tables is different from action resolution because in the former the ones digit will actually be used every time. Rolling doubles for psychic powers is the exact same probability as rolling a 9 on a d10. You make a decent point about it being used for hit location. That is a good use of the ones digit and prevents having to roll extra dice. I'd personally do 2d10 or 2d6 for resolution, which give you am extra die to work with, but who knows. Still, using the ones digit in that way is essentially an admission that it has so little to do with the skill of the player attacking that it can be safely used for determining hit location without skewing that toward low results.

And again, you fail to present any kind of relevant material. Put up or shut up, dude. Give me a quote from your textbook or a relevant study, anything. Plus, I already brought up the fact that that effect alone doesn't seem to be that important given that it could still occur on a d10 or d6. For that matter, if the effect increases as the range goes up, why not a d1000? I assume you'll say because it doesn't give handy percentages, but a d1000 gives you percentages with decimals! Even better, right?

As for whether hitting by 1% tends to be more emotionally activating than by 10%, I can perhaps only indicate a more detailed examination of the relevant material.

Sheez, this just reminded me the Sniper in our 1.5 development&testing group who had managed to get a +242(!!!) bonus to his ranged attack BS test with his Christmas-tree high-tech sniper rifle. Now that was something I call emotionally activating!

So yeah, I don't care about mechanical effectiveness or "emotional activation" - I just want my diversity and that's all.

As for whether hitting by 1% tends to be more emotionally activating than by 10%, I can perhaps only indicate a more detailed examination of the relevant material.

Sheez, this just reminded me the Sniper in our 1.5 development&testing group who had managed to get a +242(!!!) bonus to his ranged attack BS test with his Christmas-tree high-tech sniper rifle. Now that was something I call emotionally activating!

So yeah, I don't care about mechanical effectiveness or "emotional activation" - I just want my diversity and that's all.

Was there no +/-60 cap rule here? And where the heck does +2 come from?

Oh and TI none of the examples you gave have much to do with the ones digit. Nimsim mentioned the psyker thing, but hit location is already on a 10s scale (left/right limb being half and half in the range of 30 for hitting the limb). The perils table example is something completely removed from a character's stats so is a completely irrelevant example. I don't think anyone has advocated doing away with the d100 in all cases, but none of the examples you gave support retaining the d100 for characteristic tests. As has been shown, the ones digit in that case only matters 10% of the time and I personally don't see the benefit of keeping complexity that only affects the outcome 10% of the time.

And again, you fail to present any kind of relevant material. Put up or shut up, dude. Give me a quote from your textbook or a relevant study, anything. Plus, I already brought up the fact that that effect alone doesn't seem to be that important given that it could still occur on a d10 or d6.

How about I perhaps play this your way?

Since you made the first post to comment on the issue in this thread, why don't you first provide a peer reviewed study which states what you claimed:

" the ones digit actually barely even matters, because it only needs to be checked 10% of the time "

When you most likely fail at that, you may begin to realize that you should yourself look up the psychological effects which may apply to RPGs, and potentially try to use them to make better games.

Like the pure basics of the indicated difference in human perception between 9.9 and 10 in advertising, the emotional activation of 'close calls', and the familiarity of percentage apportionment.