Does Mathematical Tuning Make Games Better?

simoniker writes "What do game designers need to know about statistics? Age Of Empires DS designer Tyler Sigman focuses on statistical topics that he believes should be understood by game designers, in a new article. His reasoning: 'In the game I just finished, we recorded data from play sessions and then set challenge levels in the game based upon the mean and standard deviation values from those recorded data. We set Medium difficulty to be equal to the mean values, Easy difficulty to be equal to the mean minus a certain amount of standard deviations, and then Hard difficulty equal to the mean plus a certain amount of standard deviations.' Would all games be better if they were tuned mathematically?"

Leave out "Mathematical"

"Tuning" makes games better. Period. End of story.

Since tuning is all about improving the feel of the game to the humans who will interface with it, it all depends upon the creator for how he wishes to accomplish this. In this case, the creator was looking for sweet spots that he was able to find through mathematical manipulation of sampled data. In other cases, using math to tune the results might give the game a clinical feel; something that's generally bad for video games. (Unless you're playing Trauma Center. :-P)

So the question is pretty much moot. Creating a good game is an art form, but even art can benefit from a few structural calculations. :)

Re:

That's architecture... the blending of form and spirit, with the cold hard numbers that make it possible. A painting can be done with ANYTHING, and still fulfill it's role. If a building looks the way you want, but you forgot to carry some threes, you're

Re:

You are correct!

Mathematical tuning is a good place to start, but basing everything off of it is NOT a good idea. You always need a base point, and what better base poitn to use then some cold numbers. However from there you need to test it out and see i

Re:Leave out "Mathematical"

I'll hop on the agreement bandwagon. Mathematics alone does not make for a better game.

Case in point: I once had a cribbage game where you could play against the computer and set different levels of difficulty. I quickly discovered that "Expert" level just meant that the computer got better hands more often -- it had nothing to do with the quality of the computer's strategy. After getting lousy hands several games in a row while the computer consistently drew hands like 4-5-5-6, I simply stopped playing. While "Expert" level was certainly harder, it was also not fun to play.

So, while TFA has a point about statistics being important for game design, that's not much more profound than saying that vision is important for driving cars well.

Re:

Which game was it?

Re:

It seems like the best way to go about tuning a game would be to employ a few mathematical methods and do the rest by hand. A mathematical model is only going to be as good as the data that you put into it. There's always going to be some margin of error

Re:

well, there is quite a lot of math happening in our brains (and withing human behavior) at any given time, so this seems to be a valid approach, and the "clinical" aspects fully depend on how well you apply maths to your game (or app in general). See this

Re:

well, there is quite a lot of math happening in our brains (and withing human behavior) at any given time

That's not really "math" in the way you mean it. It's a form of computations, yes, but closer to an analog computer than a digital calculator. The brai

Re:

I disagree that tuning is just a way to work around an inferior AI. When you're only playing against the AI then tuning doesn't matter nearly as much since you can easily make the AI cheat to make up for its deficiencies. Where the tuning really matters

Re:

I would say that games with poor AI commonly use tuning to help the AI compensate against the human player, but then they also use things like giving the AI a large # of units to start with, or bigger/multiple enemy bases compared with the human's starting

Re:

BlackEmperor writes: "Is the intelligence of an object being tuned (cool)" or is the object just being given a x% production/whatever boost (sucks).

"Intelligence" generally does not have a "knob" that you can simply tune up and down. How smart a charac

Re:

Jumping in FPS's is horrible. Thank you Gears of War for eliminating the possibility of Bunny-Hopping.

Re:

grumble

Bunny-Hopping is a VERY specific thing, related to the HL engine, having to do with gaining speed due to the funky way airspeed works.

Peopel bouncing around like idiots is NOT bunny hopping, it is people bouncing around like idiots (and thus making

Re:

I agree. It's that much *sweeter* if I come top of a BF2 team with just the anti-tank guys shotgun (my fave weapon) because I know it's generally thought of as pretty poor. If all the weapons are equal in balsnce does it really matter so much which one I d

Re:

An exelent example of risk/Skill vs reward would be QIII maps. The standard required to get the rail gun is to put yourself in a compramised position (requires a LONG jump that leaves you open, place it on a platform where you have 0 cover, etc), and ofte

Re:

A machine gun is much more accurate than a SMG - as long as you are not shooting point blank.
Machine guns (light machine guns at that, 7.62 or more mm caliber) have wind adjustments on sights, can shoot cover fire at 600m, have iron s

Re:

I don't think balance is a good idea if it means every weapon, unit, or strategy has a use on every map. Maps should be unbalanced. The advantage goes to the player smart enough to figure out which weapons, units, or strategies are effective on a given m

Re:

And sometimes this needs to be tweaked. If the first thing everybody does is ignore the machinegun and rush for the RL/BFG, you may have a problem. If everybody with experience goes after the MGs soley, then you may be overbalanced the other way.

'Day of

developers

I always figured that there was some sort of mathematical tuning in videogames. I mean, there has to be a better way of balancing a game than just plugging in numbers by trial and error. Maybe its that i've played too many RPGs where math is an obvious factor, but every punch or every bullet has a numerical value right? It only makes sense to me that there would have to be some kind of number crucher on the dev team.

Re:

I mean, there has to be a better way of balancing a game than just plugging in numbers by trial and error.

It's not trial and error. It's a binary search algorithm [wikipedia.org] that executed within O(log n) time. :P

Think of it like turning a knob back and forth, getting

Re:developers

It's not trial and error. It's a binary search algorithm [wikipedia.org] that executed within O(log n) time. :P

Think of it like turning a knob back and forth, getting closer to the setting you feel is best.

That method will only deliver a local maximum of a polynomial function. If your game has any complexity at all, your proposed method is even less useful than trial and error.

Re:

Yes, however if you have ever actualy played an FPS (say HL2) on different difficulty levels you will see that ALL they do is tune the damage. I am currently playing through HL on the hardest dificulty level (after having played through on normal a few ti

You call that "mathematical modelling"?!

We set Medium difficulty to be equal to the mean values, Easy difficulty to be equal to the mean minus a certain amount of standard deviations, and then Hard difficulty equal to the mean plus a certain amount of standard deviations

Wow. If this is "mathematical modelling", then me swapping the coffee mugs out for wine glasses in my kitchen cubbard would be "advanced sphere packing analysis and optimization".

Game tuning as more art than science. The goal is not to create an interestingly distrubuted difficulty curve, but to create an "easy", "medium", and "hard" amount of enjoyable challenge. Huge amounts of time can be (and frequently are) wasted focusing too-strongly on a "cool" and intriguing difficulty model that some under-experienced junior designer is all fired up about, instead of keeping the focus tightly and solely on the how the game actually feels.

Re:

The sad thing is the article teaches people the tools but not when to apply them. For example, it introduces the normal distribution, but no tests to check the normal assumption on a dataset are given. It also ignores the incredibly important subject of

Re:

I am constantly amazed at how much game programmers know about the mathematics and algorithms for computer graphics, and how little they know of everything else.

As a graphics programmer myself (though not for games), I can say that it's really mostly g

Re:

The sad thing is the article teaches people the tools but not when to apply them.

That's going to be covered in part 3:

In the rousing conclusion to this series, I'll be taking bits from parts 1 and 2 and then putting them together in ways that actually have some relevance to games. Or I'll croak trying!

Could it be that you didn't make it to the end of the article?

I bet Easy isn't actually easy.

I'm a bit of a fan of computer games. I've been playing them pretty close to my entire life. I'm 29 now and since the days of the Zx Spectrum I've probably played at least a couple of hours a week, often much more.

Unfortunately I suck at games. My coordination is all over the place. I have NO patience. I play games for a laugh, I don't want to invest a great deal of time learning a game or practising it. I want to pick it up, play for a while, and be entertained. As a rule I always play games on Easy because I don't want a challenge. I don't want to get frustrated playing the same level over and over. I want that feeling of progression like I'm getting somewhere. I can honestly say that if I get stuck for more than an hour in a game it gets turned off and never switched on again. I make a mental note not to buy a game from the same people again.

Easy is for people like me. Lazy, good-for-nothing "casual" players who have no skill to speak of and a life of some sort that means there isn't the time to learn perfection. I expect Easy to be easy. I very much doubt that "mean minus standard deviation" of some enthuiastic professional testers or Beta players is really going to be down at my level.

Please, for the love of Mario, when you're writing a game, sit your mother down in front of it for a few hours and tweak the difficulty of "Easy" to something she can cope with. That way I might buy your sequel.

Alternatively, give me God mode. :)

Re:

I agree, and what I really like is when games take a metric (like failed attempts to complete a task) and use it to kick you to easy mode automatically. Devil May Cry is my favorite example of this. I *loved* the game on easy, and just couldn't stand it on

Re:

What I like even more is games that lower the difficulty of a given task after each, say, 3 failed attempts, and then return you to whatever difficulty you were at beforehand afterwards, or else allow you to switch the difficulty up and down without starti

Re:

What I like even more is games that lower the difficulty of a given task after each, say, 3 failed attempts, and then return you to whatever difficulty you were at beforehand afterwards, or else allow you to switch the difficulty up and down without starti

Re:

Sid Meir Solved this problem years ago: Have a whole slew of difficulty levels from braindead to impossible. Somehow I doubt he needed much math for the easiest Pirates! level, where it's nearly impossible to lose in any situation, and in a few minutes p

Re:

"Unfortunately I suck at games. My coordination is all over the place. I have NO patience."

And unfortunately, it's people like yourself that take away what makes games great: Interactivity and the depth of control and manipulation you have over you virtua

Re:

I hate automated gameplay with a passion, why not just put the character on autopilot and watch the whole game?

Angband has a fully automated AI player. While it works, it does have some quirks and sometimes gets perma-killed.

That being said, fully automat

Ever play an RTS?

You could play Dune 2, in which you must give every single unit an order. So: Click the troop, click where you want him to go. Rinse and repeat for however many you have. I think they at least attack automatically...

Or, you could play Starcraft. Click+dra

Re:

If you can't commit time to gaming

I think you should rethink the meaning of the word "game". Chess players don't want to have to play against Deep Blue every time; it's more fun to be able to play a game where you can win, and you shouldn't *have* to inv

Re:

I expect Easy to be easy. I very much doubt that "mean minus standard deviation" of some enthuiastic professional testers or Beta players is really going to be down at my level.

Maybe, but that would be a problem of not getting a representative sample. Sta

A lifetime gamer who sucks?

Alright, you do have some valid points.

One thing I should mention, some people do improve their games by making them easier -- or at least consistent in their difficulty. Jak & Daxter was mostly easy, partly because you could skip most of the game, by

Statistics to Tune

The article is essentially a fluff piece, but crammed between the useless paragraphs were occasional nuggets of practicality. The important thing to take away is that numbers are important in data models (which is what balancing a game involves.) Statist

Re:

Balancing by numbers/statistics should only be done once the raw gameplay is already in place. If you don't have a playable implementation, balance discussions are purely hypothetical with all the false dilemma and overlooked factors that implies. Once a

Too easy?

As I understand it, they are basically making 'Hard' be 'As hard as possible and still beatable based on previous user performance'. I would get bored with a game like that and stop playing it after not very long. Back in the day, I was pretty good at St

Sims Designer Chris Trottier on Tuned Emergence

Sims Designer Chris Trottier on Tuned Emergence and Design by Accretion [donhopkins.com]

The Armchair Empire interviewed Chris Trottier [armchairempire.com], one of the designers of The Sims and The Sims Online. She touches on some important ideas, including "Tuned Emergence" and "Design by Accretion".

Chris' honest analysis of how and why "the gameplay didn't come together until the months before the ship" is right on the mark, and that's the secret to the success of games like The Sims and SimCity.

The essential element that was missing until the last minute was tuning: The approach to game design that Maxis brought to the table is called "Tuned Emergence" and "Design by Accretion". Before it was tuned, The Sims wasn't missing any structure or content, but it just wasn't balanced yet. But it's OK, because that's how it's supposed to work!

In justifying their approach to The Sims, Maxis had to explain to EA that SimCity 2000 was not fun until 6 weeks before it shipped. But EA was not comfortable with that approach, which went against every rule in their play book. It required Will Wright's tremendous stamina to convince EA not to cancel The Sims, because according to EA's formula, it would never work.

If a game isn't tuned, it's a drag, and you can't stand to play it for an hour. The Sims and SimCity were "designed by accretion": incrementally assembled together out of "a mass of separate components", like a planet forming out of a cloud of dust orbiting around star. They had to reach critical mass first, before they could even start down the road towards "Tuned Emergence", like life finally taking hold on the planet surface. Even then, they weren't fun until they were carefully tuned just before they shipped, like the renaissance of civilization suddenly developing science and technology. Before it was properly tuned, The Sims was called "the toilet game", for the obvious reason that there wasn't much else to do!

Here are some questions and answers from the interview with The Sims designer Chris Trottier:

[...]

Q: On paper, a game where you simulate daily life doesn't sound that interesting. Yet The Sims is really fun to play, so much so that it is now the biggest-selling PC game ever. Although any development team working with Will Wright has to feel confident in the product they are creating, has the unbelievable popularity of the franchise shocked even the development team?

A: Absolutely. When I was first assigned to The Sims, it was not-very-affectionately-known within the company as "the toilet game." Will Wright had tremendous stamina for the risk involved with trying something very new, but there were certainly a lot of head-scratchers both on the team and outside of it. In all honesty, the gameplay didn't start to really come together until a couple of months before ship. Being involved in that tuning process, and seeing the game take shape from what had previously been a mass of separate components, was one of the most powerful experiences of my career.

[...]

Q: What makes The Sims massively popular with female gamers, who traditionally don't make up a big number of gameplayers?

A: It's so hard to answer that question without making broad, sweeping statements that anyone of my gender would probably resent. But... I can say that there are several untraditional forms of gameplay in The Sims. For instance, there are many people who spend most of their time decorating and redecorating their homes. Since there's so much user-created content being posted on websites, they spend a lot of time collecting more looks to add to the game. There are also a lot of people who enjoy having a fantasy life where they get to call the shots... for good or for bad. I've heard a lot of stories

Re:

The essential element that was missing until the last minute was tuning: The approach to game design that Maxis brought to the table is called "Tuned Emergence" and "Design by Accretion". Before it was tuned, The Sims wasn't missing any structure or conten

Re:

While I really have to apologize to the author of the game for using it as an example, 2H4U (Too Hard for You) demonstrates exactly what happens if you throw all the elements in the pot, but don't take the time to balance and tune them

to be honest, I read

Bad to do automatically

I've played games that have done this in the past and done it wrong.

Basically, the game "watched" me get better at playing a certain level of the game... unsuccessfully. But, apparently it saw that I was doing soooo well, that it decided to increase the d

my take

I'm a mathematician and amateur game programmer. The problem I have with tuning is that you aren't paying attention to the actual game design when you make stupid changes like adjusting health/damage parameters. Games can be equally hard but not equally

Tuning Wii Sports

Wii sports has a rating for your user, and changes the difficulty based on your performance.
For example in Tennis it's become noticably harder at the 500 level, while at the 0 level the computer is trivial to beat.

I think satisfaction happens when the game

Jagged Alliance 2.x

How would you ever tune this game? I have been playing it for nearly five years, including all of its mods and new developments. Tuning it is nearly impossible because the tactics employed by new players are so vastly different from veterans that I cannot

how else are they tuned ?

in an environment ultimately based on 0/1, by flavor ? :D

Re:

What does this have to do with gameplay tuning?

Re:

What makes you think this is an "Ask Slashdot"?