What exactly are the demographics for The Sims?

The demographics for The Sims are very broad. Like most games, they're still centred in the 15 - 25 year old range. We have a lot more females than is typical. Our age ranges, though they taper as they go up, go way up; there are a lot of 40 and 50 year olds playing The Sims. I think that a lot of our players are people who don't play many computer games -- if any. For a lot of people this is the first computer game they've actually really gotten into. Usually, the pattern has been that the hardcore gamers buy it, bring it home, and show it to their spouses and the rest of their family Then, frequently, their spouses, their wives, or girlfriends, or kids will start playing it, and really get into it more so than the hardcore gamer that brought it home.

Did you imagine that The Sims would be so popular with women?

I thought it would be popular with women, though I didn't think the game would be as popular as it has been, period. I always thought that the female attraction would be there because, in fact, something like 40 percent of our development team was female. I don't think that you can really target the female demographic the way a lot of people have tried. I think that what we really need to do is make better games. Females, in general, are more discriminating in their entertainment choices. So, as the quality of games goes up, I think that's one of the main ways that we're going to hit more of the female market.

Are there ways to make a game that women are more likely to enjoy?

The other way is to get a lot of women involved in the making of the game. For me, so far, this has been the only sure-fire way. You know, if half of your development team is female, I think it's pretty unlikely that you're going to end up with a really testosterone heavy game - if they have some say in the design.

The Sims seems to have the power to alter a player's viewpoint on life. Recently I've been feeling somewhat paternal, but after having a baby in The Sims, I'm strongly reconsidering.

(laughs) That's interesting. A lot of people get the surface level stuff, where they walk around for the next three days saying, "Hunger negative 20." They start mapping their motives to The Sims.

That was kind of another thing that was really meant to be more of a parody, but in fact I went around my house looking at all my objects, trying to figure out, "What's the least number of motives or needs I could put that would justify all this crap in my house? There should be some reason for everything in my house, what's the reason?" So, it's really altered my perception at that level.

What exactly are the motives or need mechanisms in the game? How did you decide which need mechanisms were important?

We have eight needs: hunger, hygiene, bladder, comfort, energy, social, fun, and room. For every Sim, these are the bars that are going up and down.

We started by looking at all the objects that we wanted to have in the game, and saying, "Okay, what's the smallest number of needs that we could use to justify all of these?"

We were basically working roughly from Abraham Maslow's Pyramid of Needs. Ours is much simpler, but it's the same basic idea; you have these base needs like hunger, and shelter, and safety. Once you've met those base needs, then you can start working on your higher level needs, which have to do with things like socialization and/or family. Above that, the highest level needs are what he calls self-actualization -- you know, self-improvement. Basically you're not going to be worried about self-improvement when you're about to starve to death, or a tiger is running you down.

Are there any actual need mechanisms in the game that we don't get to see?

That's a good question. Not really, although sometimes we misuse the ones we have. Basically, the objects advertise to the needs of the player. So, a refrigerator advertises hunger, the toilet advertises bladder. Occasionally we'll do false advertisements, like when the phone rings -- it's promising things that it doesn't necessarily deliver. It's promising things like fun and social, although until they pick up the phone they have no idea what they're going to get. They go answer it is because they think they might get social or fun. So, we trick them into picking it up, and then they might get social, they might not.

Once a specific need is fulfilled, how do you stop the characters from changing their behaviour every couple of seconds?

You can view this whole process as climbing this happiness landscape. The advertisement that an object presents to the character can be based on the object state, character state, or the character personality. For instance, a chessboard might advertise more fun to a serious Sim than to a playful Sim, whereas a pinball machine might advertise higher fun to a playful Sim.

The amount of fun a Sim actually gets advertised to it depends on factors such as the distance. The advertisement attenuates with distance, so something very far away -- a pinball machine very far away -- doesn't advertise very much fun. The objects can also decide on how steep that attenuation is. Something like a bed can advertise pretty highly over long distances. Objects can also be unique to a Sim; Sims can have relationships with particular objects based on use. So, if you have a Sim sleep in the same bed over and over, it will start developing a relationship with that bed -- they'll decide it's their bed. That will be added on top of the advertisement, so their bed will advertise much more than somebody else's bed. If for some reason their bed is occupied, they might sleep in somebody else's bed, but they will almost always prefer sleeping in their own bed.

When you look at these motives --these needs-- they're worth a lot more to the happiness. if they're very low. If my hunger is negative 20, I might stop at the fridge and grab a snack. If my hunger is negative 80, I'm not going to look at any other advertisement -- at that point the hunger is worth so much because I know I'm about to starve to death. We have what are known as contribution curves; each need has a unique set of curves associated with it saying that this is how much you really worry about hunger at these different levels. That way if most of their needs are fairly high but one is very low, they'll really concentrate on the low one.

These curves also vary by character type. The adults have a different set of curves than the children. The children tend to value fun more, on the high side, than adults do. So, their curve for fun keeps going up, whereas adults, once their curve gets above 50, it gets a little bit more level.

Generally, the first question we're asking is "what prevents them from being stranded on a local maxima?" I have a need, I go to meet that need; the reason that I'm not stuck on the local maxima anymore is because in every case what happens is that I go to the fridge because I'm hungry, I open the fridge, I eat a snack, and all of a sudden I'm less hungry. When my hunger level drops, then the peak I'm standing on collapses, at which point I'm now on some other slope. Then my next behaviour will be driven to whatever the next outcome most likely to increase my happiness. Basically, they're looking at all the activities that they could do at any given time, and they say, "Which one of these activities is going to increase my happiness the most?" It's a fairly complex algorithm to determine that, but it's based on what their current needs are, their current state, all the objects around them, and all the people around them. This is exactly the way the people relate to each other also -- the people are actually advertising to each other; social usually.

Do you find that this type of AI is far more complicated than the usual game AI?

Not really. In some sense it's quite a bit simpler because if you took more of a standard procedural approach to this, the tuning of it would be almost impossible. Also, it would be very difficult to expand it. The tack we took here was that the Sims will have very little information about the environment and objects around them. There's this standardized kind of negotiation, and that's what I've just described to you, these advertisements, it's about all they know about an object. When they actually decide to do an interaction, like go get a snack, they actually start running code in the object. So they would say, "Okay, I like this one advertisement the most, so I'm going to do that one." At which point, you could almost do this like a program counter, and then the program counter is actually jumping to start executing code within the fridge. The first thing that code says is, "Walk to me, stand in front and face me, then run this animation, play these sound effects, do whatever." This way, we can add new code, new levels to the simulation, even new simulation layers, just by dropping in new objects into the environment, and they automatically know how to deal with them. To get that level of expandability in a more procedurally based system, I think would have been God awfully hard.

In terms of videogames, do you think that players really have a right to privacy? They are installing someone else's software in their system after all.

I think everybody has a right to privacy -- to some degree. There are a lot of things that you could do in a videogame in terms of tracking your habits or things that might even extend outside the game. I don't think that this is anything in particular to games; I think that its probably more of an issue with websites.

I think that people do have a right to privacy, but on the other hand if you want to play a multiplayer game, the server's going to have to know your IP. If you walk up to a public place and do something, I don't think that you can expect privacy because you're in this format, this forum, you're in a public space. Certain online activities are more like being in a public space, where purely for technical reasons you can't expect total privacy.

Are there effective ways to combat computer piracy?

Probably one of the best things that you can do is give the registered users a lot more value for their money. So that if you register the game you get more than a pirate would get. This is something that we tried to do on The Sims with the downloads. If you bought the game, then you can come to our website and register, and put in your name, and your password, and all that. We keep track of how many registrations there are per real copy, so we know for every serial number of the game how many people have tried to register under that serial number. We provide a lot of add-ons -- these are objects you can download to the game such as new skins.

At some point it really becomes about community management. If you're doing a good job supporting the community, then the community actually helps you actively fight the pirates. One of our guys, Andrew, ran one of our websites. I think it was SimEden. He organized an anti-piracy campaign after The Sims came out where he was going around, surfing the web, reporting the warez sites, and trying to find cracked copies just to report them. He got a lot of other webmasters to help him do this; this was with no encouragement from us whatsoever.

We had been actively dealing with these webmasters for about a year before the game shipped. We actually started this thing where we got the 20 best SimCity webmasters, we asked if they wanted to be on this mailing list, and most of them said yes. Every week we would send an email to this mailgroup telling them what we were doing that week on the game, and features we were thinking about adding or cutting, and they would write back and give their opinions of it. We got them very actively involved before the game was finished, you know, while we were still working on the game pretty heavily. At the same time, they were building websites around the game very early on. Eventually we started releasing tools for custom content that they started using, again, many months before the game shipped.

Basically, we got those people very involved. They had as much investment in it as we did because we were sitting here spending all this time building the game, but they were spending all their time out there building these websites and custom content to the game. When the game came out, when there was piracy, they felt like they were being pirated, not just us. They were kind of like part of the development group. So by building that into the community, I think we ended up with this very strong community. A lot of times people would come onto our bulletin boards after the game shipped, asking, "Who's got a serial number I could use?" They would just get blasted by the real fans out there.

How important is the online community?

Oh, it's vital! Absolutely vital. The Sims is not a multiplayer game, but the online community is probably half the experience of The Sims because we designed it around this heavy customization, storytelling tools, and all these things. So, really one of the most entertaining parts about The Sims is sharing what you've done. Either you've created these cools things, or this interesting family, or you've built a really neat house, or you've told a neat story and put it on The Sims website. A lot of people play the game, and for a while they really get into it, they enjoy it, but at some point they flip over into this community mode where they start talking to other people about strategies or they start creating stuff and putting it on the website. Other people download that and create something even more out of it.

Really, something like The Sims is much more like a hobby, like a train set, than it is like a movie. Most games are built under this movie metaphor, whereas The Sims is really under this hobby metaphor. It's really a shared experience, but each person can take their particular slant on it. If you look at people that are seriously into train sets, a lot of them are just into the train or the way the mountains are sculpted. Other people are into the switching logic or the little village. Yet, they all come together around this one activity, and they have different talents too. This is the type of thing where my talent can really leverage off your talent; if you're really good at making mountains and stuff, and I'm good at laying out the tracks, then we can work together make something better than either one of us could on our own. You see this a lot on our website where people upload these stories, and there are very good writers, and some of the stories are very interesting. A lot of times they're made out of a lot of custom content that other users made and put on their websites. It's kind of the users downloading the other users' stuff, and combining it in other ways to make new things.

Is this why you constantly put upgrades on the website?

The primary thing that sells games is word of mouth. Basically, the longer somebody is playing a game, the longer they'll be talking about a game, the longer they'll be showing it to their friends and family, the longer somebody might just trip over them playing the game and say, "What's that?" Anything that we can do to increase the amount of time people spend playing the games will, I think, increase sales.

I was actually doing some simulations for the hell of it -- some epidemiological simulations. It's kind of interesting, if you take a virus and you just double the period of time that it's contagious…rather than you being contagious for one week, you're contagious for two weeks, its spread into the eventual population is totally non-linear. So, in fact the eventual spread of the virus could end up hitting five times more of the population than if it were half as contagious. There's a tremendous leverage that you've got there. I think that games are somewhat like that, where if I play a game for one week, I'm going to spread it to so many friends; if I play it for two weeks, I'm going to spread it to a few more. That means that each of those people is going to spread it to a few more, and a few more, and so it's compound.

I think that it's one of the best things that you can do, especially if you're doing a game that is targeted towards a more casual group. With The Sims, I think a lot of our players were first time computer gamers. If you think back about it, you know, how excited you were when you first started playing computer games, and imagine someone experiencing that for the first time -- they're probably going to be much more vocal about what they're doing. They're going to be much more excited about, "Wow! Look at this game! I never thought I'd play a game before! I've got this game that's really cool because you can do x, y, and z." So, they're just going to talk about it more. That's another degree of compound leverage.

What is it about The Sims that appeals to the first time and casual players?

Probably a lot of things. The most obvious thing is that it's about an environment that they understand. It's not about magic, or purple dragons, or esoteric military hardware, or some hardcore sports thing; just about anybody can relate to this. Secondly, we designed this thing to be very projectable: it's really easy to project yourself into the game. There are a lot of things that we leave unstated, or that we deal with a fairly abstract manner, such as the way that the Sims speak or the way they look. You can't actually see their faces that clearly, which makes it pretty easy to grab one that looks relatively like you, and then imagine it's you. Whereas if you could zoom in very close, you could clearly see that it wasn't you, and it would be hard to maintain that illusion.

I think these things add up to somebody being able to project themselves into the game very heavily. They can imagine themselves being there, and it's also a situation that they can imagine. They can put their house, their life, their family into the game. Because of that, it drives a lot more empathy with the characters and the situations. Also, it's a familiar environment, but yet they can be very creative with it. They play with the game for a while, but later they shift into more of a director mode, or a storyteller mode. At first, I think that people are just kind of reacting to the simulation, and trying to make money or get a job or whatever. After they get a little more familiar with the game, then they shift more into a storytelling mode: "Oh, I'm going to see if I can do Gilligan's Island, or I'm going to do Mary Tyler Moore living next to the Bunkers." I think to a lot people it feels kind of like interactive television.

What sorts of skills do your games develop in your players?

The one thing that all the Sim games really emphasize more than anything else is the shape of chaos. You can have what seems like a fairly simple system, but even a few simple things interacting can lead to wildly unpredictable behaviour. Sometimes, it just takes one little nudge in a different direction to make the whole system flip states. In SimCity for instance, there's kind of an old saying in urban planning that roads don't solve traffic, they breed it. That's due to strange, chaotic nature of ways that cities develop that doesn't seem apparent at first, but when you start playing the game, you start getting a sense of how a lot of these issues just aren't as simple as they seem.

Life is similar in another way. Every day is different, but it's the same in certain regards. But just one phone call, or one little thing changes, and all of a sudden the course of your day can change dramatically. We tried to push that to extremes in The Sims; we didn't want every day to be the same, so we always had little things that nudged the system out of it's current state.

Where did the idea for The Sims originate?

The original inspiration for the game was on the architectural side: it was inspired by the work of Christopher Alexander who wrote several books on architecture. Probably his most well known one was called The Pattern Language. He's an interesting guy because he was fed up with the way architecture was being practiced, which was more about form, and colour, and art. He was trying to return back to the roots of architecture, which is how environmental design can change our behavior -- behavioral based architecture as opposed to aesthetic based architecture.

I was really interested in how a game could possible show how the design of something could impact the way people behave and live within it. I think that's a deeper lesson that I would hope that a lot of people take away from The Sims. Even so, it's not necessarily that a building that would work well in The Sims would work well in real life, but just the fact that there is a real link there between behavior and environment.

One of the biggest things that I wanted to show was how, basically, the real resource everybody has in life is time. You can convert time to a lot of other things -- you can convert it into money, objects, and friends -- but how you choose to spend your time is how you're playing the game of life. That's the one thing that you don't get more of, really. So, time management was a big thing I wanted to at least make people more aware of. It's not so much preaching, "Here's how you should spend your time." It's just interesting when you sit back and think about how you choose to spend every minute of your day.