I am wonder what people think are the pros and cons of the fixed and variable target number systems?

i prefer variable. it allows for things to be incredibly difficult and unlikely, but never impossible.

that being said, i feel SR3 allowed the TN to change too freely... some things should have been handled in ways other than changing the TN IMO, so that you don't end up with crazy TNs that no one can reasonably expect to hit all the time.

(i mean, if we're talking about your being grappled and trying to shoot a gun at extreme range and you're blinded and drunk, then sure that should be almost totally impossible... but just because you've scratched your knee, the difficulty shouldn't go from 1/2 to 1/3, and let's not even consider the possibilities of things like chaotic world, which can basically make a group of people totally useless).

so i would say variable TNs, but probably not the SR3 system exactly.

Voted variable, which is not a good word to describe the results you'll get by posting this thread in the SR4 forums.

I'm forced to wonder, in discussing target numbers, given the choices of "fixed" and "variable", what exactly could be "other"? Some sort of quantum target number?

Anyway, I actually prefer fixed numbers in practice. As far as raw rules theory, I think variable target numbers are best. They allow considerably greater variation in probability. The problem, theoretically, with fixed TNs is that 2 successes is always the same amount less likely than one success. All that said, I've found that the games I've played using fixed TNs flow much better. Old World of Darkness games got bogged down very easily, whereas, for one reason or another, nWoD games are very smooth. Same for Shadowrun. My limited experience with pre-SR4 Shadowrun was a struggle between me and the system. SR4 is much easier for me to work with, in part at least due to fixed TNs.

I null voted because they're both good. SR3 and D&D work well with variable TNs. Sr4 ad nWoD work well with fixed TNs. I'm slightly in favor of fixed TNs because as Eryk said they flow faster. Unlike some people I like that fixed TNs can make some things impossible. While theoreticaly all things are possible, that grappled long range blind and drunk shot is so incredibly improbable that there's really no reason to roll dice, hence the game moves faster.

the problem, to me, is that the grappled + long range + drunk shot is only impossible until you breach a certain level of ability. at that point, you suddenly have a 30% chance of making the shot, and the probability only goes up from there. under a variable TN system, the shot remains extremely improbable all the way from 1 die up to any conceivable level of ability.

You have a 30% chance of getting a hit. You don't have a 30% chance of making the shot. One hit on a test is rarely success.

The problem mfb and other rules-lawyer-y types (including myself on occasion) have is that nowhere does it tell you that the threshold is higher than 1. It just says "have the GM decide" and leaves it at that. Thusly, the "by the rules" answer is that you only need one hit.

the system still breaks down past a certain level of ability, McMurray. thresholds just raise the level you need to breach before the 'impossible' becomes trivial.

Exactly, therefore, as long as you keep raising the thresholds with the level of 'impossibility' then everything stays hunky dory.

and then we are back at the silly armsrace that was high skill/karma SR3...

to me, the game should be so that, unless we are moving into the realm of action movies or comics, in no way should a person be able to make a shot while drunk and being grappled. its just so far out there that it may well be a deus ex machina moment...

Being grappled stops you from making a shot anyway. It was an example someone used, but it isn't a valid example because if you're grappled you can't take any actions that require physical movement, including aiming a gun.

Average person: 2 dice. can't hit a small target to save his life

Average Shadowrunner: 8 dice. Can hit stuff but when the crap hits the fan he's in trouble.

Gun Bunny: Average 15 dice. He's a bad mamma jamma, capable of hitting things in the craziest of circumstances.

Twinked Gun bunny Adept: 20+ dice. His ability to shoot things is magical.

As long as thresholds and dice penalties are scaled to the task, making the impossible possible can be done but not with ease. If they want to shoot something while drunk and blind they're at somewhere between -8 and -12 dice depending on how drunk they are. To average people that's impossible.

The gun bunnies can do it but they've got the benefit of cyberware and magic. Their smartlink isn't drunk, and their agility is such that being drunk isn't as much of an impairment to them. With the adept it's even better, becuse his smartlink isn't drunk and neither is his magic. He slurs a thought of "shoot that bastard" and his "guiding force" or whatever he calls his magic takes over and tries the shot for him. It's working alone, so isn't as capable.

I'm willing to bet that if you dig through police case files you'll find at quite a few cases of drunken armed guys managing to get a shot off while being wrestled to the ground by a cop. Some of those will hit his grappler of another cop. Some of them (the critical glitches) will hit the drunk guy.

well, i voted fixed. i do have an idea for getting 'other' to work however.

Simply put, you TN is based on your skill. this way, a skilled person gets more hits than an unskilled person using a higher stat, even if dice pools are the same.

So, unskilled hits on a 6.
skill 1-4 hits on a 5 or 6, as normal. (or when no skill is required, like will and body)
skill 5-6 hits on a 4, 5, or 6 (possibly include specific non-skilled rolls that include a specific positive quality)
skill 7 hits on a 3, 4, 5, or 6.

5-6 is limited at chargen, and you CANNOT do this with skillwires. so its balanced in that any starting character may only have 1 or 2 rolls where they get this bonus.

7 is best in the world, and only 1 skill of this level per person. so thats balanced, and explains why fastjack is so bloody good. It makes having a high skill actualy mean something, other than just more dice.

So the TN is fixed, but what that fixed TN is depends on your skill level.
we could further balance this, by saying you cannot use a 'skill' level higher than your final modified dicepool. If your making a roll with only 4 dice, then its 5 and 6 only.

S you roll your skill in dice and get more hits with a higher skill? Way too poerful at the high end IMO. A 4 skill can expect 1.3 hits. 5 = 2.5 hits. 7 = 4.6. If you're rolling stat + skill like in SR4 or there are ways to get extra dice (i.e. smartlink) the disparity is even greater.

you'll find a lot of crazy things if you dig through old police files. most of them are covered by Edge. that's another argument, though.

the problem with fixed TNs is the sharp rate of change in probability. you go from 0% (no dice) to 30% (one die) with the application of the smallest possible modifier (+/-1 die). higher and lower thresholds do not lessen the steepness of this jump, they just raise or lower the point at which it occurs. there is zero differentiation below that point--a guy who's never picked up a gun before and a guy who's trained every day of his life have exactly the same chance of success, if they're both below that threshold. meanwhile, a third guy, who has trained every day of his life and has a smartlink (or other means of acquiring a small bonus to his dice pool) has stands a reasonable chance of making his shot. everything above that point is just gravy, be it adept powers or whatever.

So the fact that there's a difference between a newb, a veteran, a cybered veteran, and an adept cybered veteran is a bad thing?

no, the fact that there is no difference between them, if the threshold is high enough, is a bad thing.

and there are points where not amount of skill and gear can help, thats when edge or pure luck kicks in...

but noone should rely on luck for long, unless its that welldressed disney duck...

if you like, have the them roll edge dice if they drop below 0 normal dice, but have each hit only count for 1/2. so that you need 2 hits for each effective hit

eh. i don't think there's any point where ability completely stops being relevant.

maybe not, but there is a point where its so minimal that it plays second string to dumb luck.

but each their own.

i think this debate have gone the rounds atleast ones before...

btw, mfb. sometimes i wonder why your posting on the SR4 part of the forum. from what i gather you dont like the new system what so ever...

IIRC he doesn't even play SR4, he just comes here to gripe about how bad it is.

I'm going to agree with McCurray that, as long as the proper threshold is set, the impossible/piece-of-cake leap I think mfb is talking about is not too much of a problem.

The book suggests a threshold of 4 for "extreme" tasks, such as the one being discussed. According to Shemhazai's odds calculator, the chances for success on a 4 threshold test are:

3 Dice=Impossible
4 Dice=1%
5 Dice=5%
6 Dice=10%
7 Dice=17%
8 Dice=26%
9 Dice=35%
Etc.

So going from impossible (3 dice) to possible (4+ dice) does not immediately give you a huge leap in success chance.

If you don't like the idea of impossibly, there's always the option of not modifying the dice pool and increasing the threshold instead. Now, as Tarantula said, some people may not like this too much because it's not the "official rule" (even though it's suggested in the rulebook.) Personally, I think that if one doesn't take advantage of this alternative, he is missing out on part of the system's versatility.

one might ask why a question regarding dice systems is in the SR4 forum, when SR4 has a dice system already in place. i'm going to answer this question for the last fucking time: i read and post to the SR4 forums because i like SR. i am not pleased with the game mechanics of the new edition. if you don't like that fact, or would like to take issue with it, or if you have any questions regarding this statement, i invite you to bite my cock. if you're not a fan of having that thrown in your face, i suggest you stop throwing the fact that i don't choose to play SR4 in mine. moving on.

Little teste lately?

that is, indeed, a common example. luckily for me, i'm talking about net dice and successes.

Right, mfbs point is that there is a very large discrepancy between the "you aren't allowed to try" and "roll 1 die and have a 33% chance of getting a hit". Which there definately is. While the threshold mechanic does get to step in and help govern against this, it doesn't negate the fact that its there.

To you mfb, to show a similar example in the variable TN method... TN 6 = TN 7. And there isn't any mechanic to help even out that, its simply fact. Same with 12/13, and so on. So no matter what system you're using, it'll have its own individual breakpoints. At least the fixed TN has a mechanism to govern its and smooth out the percentages a bit.

the TN 6/7 leap is admittedly a problem. it's one that's easy to fix, though--and the leap is nowhere near as large as the 0-30% leap. the question i'm asking is, "is the progression smooth?" in most fixed-TN systems, the answer is "ow, my shins, i bruised them"; and in most variable-TN systems, the answer is "wheelchair-accessible, if slightly bumpy".

Yes, but in your comparison, you're ignoring the compensating mechanic the fixed TN has to smooth out the bump. Why? I'm not really sure, maybe because the variable TN has no such mechanic?

i ignore thresholds because their use is poorly-defined, at least in SR4. thresholds are going to vary wildly from gaming table to gaming table for the simple reason that they are one more thing for the GM to remember--some GMs will, some GMs won't. the players certainly aren't going to remind the GM to apply thresholds to their tests. if thresholds were defined concretely for every test, the way TNs and modifiers are in SR3, it would be easier to take them into account. thresholds that are integrated into the system can, indeed, help smooth things out.

done properly, any dice system can work just fine. given a proper fixed-TN system and a proper variable-TN system, i personally would have to flip a coin to choose between them. even a single-die system can work perfectly well, if it is done properly. for instance, one important goal is mitigating the severity of outliers, either by making them less common (by using more dice) or by making their consequences less extreme (by adjusting base values, such as in a hit point system).

Want fun? Sometimes I throw thresholds into variable target number system tests. MMMmmmm MMMMMMmmm GOOOOooood.

(Which, admittedly, is nothing new or all that outrageous. However, it's late, I'm tired, and I enjoyed typing it.)

last time i checked, a treshold is defined for the areas where fanpro tought it be important (assensing and similar), while left the rest up to a ladder that defined one place, the chapter that lays down the basics of the dice mechanic. write that down or memorize it and presto...

still, i find myself just having the people roll and then "guesstimate" the outcome based on the number of hits. but then i have a feel im not the kind of GM mfb would like to play with...

btw, i see the page james linked to is hosted at ntnu. interesting

i'll try my hand at explaining why i think a slightly more "set in stone" set of rules is good (sometimes).

simply put, people who don't like the set in stone rules are often experienced gamers. they can much more likely make accurate guesses about what changes will have what effects, what will make something too good, etc.

in comparison, the gaming system also has to be set up to handle people who cannot do that, either because it's just something they have no gift for whatsoever, or because they are completely new to the game (or gaming in general), or they don't have the backbone to enforce rule 0 (the GM is always right) without a rule written down in the book to back them up.

so, just saying "it's up to the GM" means that the effectiveness of the system is going to vary from table to table. your GM will handle things completely different than mine, and vice versa. however, the problem with this is, if my GM is one of those people who just has no gift for on the fly adjustments (and yes, such GMs do exist, and in my experience, are much more common than many people seem to think) is that for the game i am in, the system simply does not work (or rather, works the way mfb has pointed out). this is also going to apply to just about any group that either decides to get back into SR after a long absence, or who are just starting out SR4, and have no one experienced to guide them.

basically, any system can work fine if you have a GM who forces it to work. but said GM is not the one you're worried about. it's the new GM who's unsure of his decisions and needs guidance and direction that the rules should be written for, since said GMs are much, much more likely to be using the default rules than a more experienced, confident GM.

oh, and iirc, the TN 6 = TN 7 problem had a solution if you used the shadowrun D8 system that was presented in TSS a long while back.

@mfb
I see your point, and in many cases I liked the SR3 system but for different reasons. However, your complaint about the 0-33% jump is missing 1 crucial piece of its analysis: opposed tests.

Remember that SR3 was based off of: 1 success = you succeeded.
When doing your comparison analysis remember that the new paradigm of SR4 is: 1 net success vs. your opponents roll

So, yes some gun bunny might have 0% chance and some gun bunny with a Laser Sight might have 33% of getting one hit. However, if he's shooting at even an average person (REA 3), there's a good chance that the 1 Hit won't do anything anyway.

So, keep in mind when you rant about the base 33% Probability that the SR4 system now fundamentally depends on the opposition of tests to "normalize" it probabilities.

opposed tests are merely another form of threshold. the opposing roll presents a threshold of (opposing successes) to your own roll. it's variable, yes, but the success rates are flat enough that the effective threshold provided by an opponent's roll shouldn't often come as much of a surprise. and in the end, it doesn't matter if the threshold of 4 on your test is imposed by GM fiat, a table in SR4, or an opponent's roll.

The success rates are flat enough on paper. Have you sat down and just roll a bunch and looked at the variances? The whole fact that each die has a 33% of counting (a fairly significant number) means there will be a fair amount of variance in the Thresholds.

Basically, in SR3 there are variable target numbers. In SR4 there are dice modifiers and variable thresholds (based on game situation or opposition rolls). Poe-tate-o, po-tot-o.

so maybe instead of having a static treshold one should roll x number of dice depending on how hard one think the task should be. kinda reminds me of the system west end games used for star wars...

Yeah, statistical probabilities on those 33% dice rolls work out over a large sample, but each individual roll is unlikely to come out to exactly 1/3 of the dice being hits. Having played quite a bit of SR4 I can say from personaly experience that even 12 dice will sometimes fail to get 3 successes, while sometimes you'll get 6. Getting 4 on the nose is pretty rare. It's the same with variable TNs. What the percentages say don't really matter in one roll.

whether they're flat or not is irrelevant. the threshold exists whether you roll it up on the fly (as in an opposed test) or get it from a table in SR4, or get it from GM fiat. thresholds generated from opposed tests are going to fall within a certain range, anyway--minimum of 0, maximum of the number of dice your opposite is rolling, mode of 1/3 the number of dice your opposite is rolling. if your dice pool is less than the mode, you're going to be SOL 2/3 of the time whether you're defaulting or whether you're Captain Fantastic.

almost any system, with the magnification dialed back far enough, leads to a probability curve that looks like a cliff. on the low end, you are in the abyss--no matter how much better than the other people in the abyss you are, you have no chance of success as long as you are also the abyss. on the other side, you've got the plateau. once you're on the plateau, it doesn't matter how much better you get--you've already won. differentiation is meaningless. in between these two extremes, you've got the 'cliff' itself. in a good system, the cliff isn't a cliff, it's a gentle slope--a very long slope, because this is a game and winning games is fun and 'winning' in RPGs means, at least in part advancing your character (yes, we all know that interesting RP is also 'winning', and that different people feel differently about which one is more important--but a good RPG will satisfy both types). you want a lot of room to grow. you want a gentle slope because as you grow, you want the growth to reflect the amount you expended to achieve that growth--no jagged steps where advancing a small amount once gets you a little bit of growth, and advancing again gets you a huge amount of growth.

a well-constructed fixed-TN system can offer that room, and that gentle slope. so can a well-constructed variable-TN system. the question is whether or not the system is well-constructed.

no, you didn't. as i said, a good system will satisfy both types of players.

well, it takes quite a bit of hard work, sure. i suppose in a general sense, luck factors into the joining of various factors that contribute to a mindset willing to put in such work.

i put those guys in the other group. the rewards they're seeking have less to do with character advancement and more to do with having an advanced character. which is more an RP thing than a system thing.

I'm trying really hard mfb but I still can't see what you think is so "broken" about SR4. I have to come back to the opposed test. The analysis of probabilites gets much more complex when you throw this into the mix.

When you are examining your SR4 probabilities you can't just say 4(or 3) SR4 dice = 1 Hit. If that is how your analysis is done then you are flattening the probability curve, not the system. Just to be sure I'm reading you right, is this what you're doing:
PC dice pool = 6
Task threshold = 1
Avg. opponent hits = 1
____________________
Threshold <= 6, 33% chance of success.
Threshold > 6 0% chance.

If that is how you are looking at it, then your analysis is flawed. By "averaging" the opponent's hits you are flattening the probability. If you sit down and roll it out 3 (or 4) dice is far from a guarantee of 1 Hit. Now, because of this variability the SR4 system doesn't "graph" well when examining tests, it will seem very erratic. Depending on how lucky your opponent is, a task can swing from "trivial" to "impossible." That variability, IMO is called "fun."

no, here's what i'm doing.

PC's dice pool = X
task threshold or opponent's actual hits = Y
dice pool modifiers = Z

if Z brings X to less than Y, X no longer matters--it may as well be 0. X could start out with a value of 1, or a value of 100. as soon as Z reduces X below Y, X becomes irrelevant; you fail, or you use Edge, and Edge is completely independent of X. the only thing Y does is raise or lower the point at which X becomes irrelevant. if Y is generated by an opposed roll, that just means that in any given roll, the point at which X becomes irrelevant is variable. that point might be reached in a given roll, or it might not.

the net result of this is that a guy who's defaulting to an Agi of 1, and a guy with Agi 3 and Pistols skill of 3, are both equal if the dice penalties on a shot add up to -6 or more.

And there is a problem with something being unable to attempt something with your skill, but rather relying on your luck?