# Interstellar Economic Simulation

I'm designing a game reminiscent of Elite or Escape Velocity, those old space trading games, where you play a traveling merchant in space.

I'd like to have the game's economy at least resemble a real one. What resources are available that I could look at to get an understanding of the algorithms I'll need to perform the simulation?

One big hurdle is that I'm pretty horrible at math; so a simplistic explanation would be ideal.

I figure an interstellar economy wouldn't be all that different from a global one; certain things can only be manufactured in certain places (due to resources and technology levels), shipping things takes time and money, people in different places need different things... just instead of cities, they'd be planets.

A Google search of "economics simulation algorithm" and similar terms turns up little of use, and nothing I've got the background to understand.

Anyone know of any useful resources I could look into?

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No offence, but if you aren't strong in math, I fear the result might be boring or downright broken... wouldn't you better find a game designer who could help you doing that? – o0'. Mar 30 '13 at 22:05
I have no idea about existing algorithms in this area, but don't forget to consider things like cost of labor when creating your economy model. – Benjamin Danger Johnson Mar 31 '13 at 5:18
Not algorithms so much as basic economics, and @Lohoris is right in that you will need some decent math so that your systems don't explode, implode, or just plain not work. – Patrick Hughes Mar 31 '13 at 16:35

Modelling something that is near impossible to do "right" but you can give a reasonable model of the economy (eve online is the most successful close match I can see that matches what you're trying to do)

For example:

Product A in Region A might be of low value because there is lots of it and getting it to this region is cheap. Product A in Region B might carry a higher value because it's not so abundant in that region and thus has the cost of being transported to that region.

Now depending on how your game works, if a player can buy a product from a far away region from anywhere in the galaxy then price displayed should be offset by your transportation cost.

Key things to note:

• This is a very simplified starting point.
• Transport costs may vary (think about risk, cost of other commodities like fuel, ships or ship parts).
• Tax ... are you planning on having that in your model?
• Abundance, any resource a user can just go and make / mine for easily should be worth virtually nothing as it would be simple to flood the market with such a commodity but with that said if no user is doing so and the demand rises then the price should rise.

What I find works best when im playing a game is models that shift by themselves. Each and every transaction that takes place in your market will have a knock on effect not just on the thing that was being traded but to the market as a whole. Links to products on a market can effectively be traced to virtually every other product on that market ...

Look at the real world, a barrel of oil makes more than 1 product, from fuel, to plastics.

any industry that depends on any of those products would be affected by the price of oil. but the oil drilling industry needs things like drill bits so will be affected by the price of say diamonds, metals, ect.

But metals need to be proccessed before they can be used and then manufactured in to drills so the metal workers need oil.

And that's a very basic example, when you consider something as complex as your mobile phone it goes completely bonkers.

Start with a table that contains all your products and give them an arbitrary value (don't worry if your model is any good this should sort itself out later).

Now set a load of rules and implement a method / function to implement them.

• rule 1: a product on the market increases by X amount for each system you have to go through to get to the nearest location it can be found
• rule 2: the higher risk to move a product between 2 systems offset
• rule 3: value by X rule 3: offset value by available / demand

Now you can write some sort of GetPriceOf(Product product, Location system) type function that determines based on the output of a chain of rules what the price of the given product might be in the given system.

Then just keep building and building on it until the model feels real. It'll likely never be perfect, very few companies actually get it right and even when they get it right it's still not real like in the real world.

The other thing you could try is making money as hard to come by as in the real world then based prices on the real world stock market ... could be a bitch to wire up to your game though.

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That does sound like a pretty good plan. Ultimately, I suppose what I really want is a system that approximates reality well enough that strategies that work in real life work in the simulation. Perhaps the best thing to do is just try things until I hit upon something that feels right. – Schilcote Mar 31 '13 at 23:21
what I found works well is where a game has a lot of automation in it to balance any "twisting of the market" that a user might do ... for example a user might buy up a lot of a really cheap product in order to have a knock on effect of a more pricey product that they already own a lot of ... if the market could "handle" that sort of scenario then it's likely to be reasonably good. The best way to know it works is to break it ... if you can't break it you're on the right track. – Darth_Wardy Apr 1 '13 at 22:23

You can create a "flow of merchants" system which edits the routes' popularity based on the length of the journey and the income and adjusts the prices according to the amount of goods transported there. In other words, simulate other merchants(not individually, but via "popular routes") that influence the economics as much as you do.

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Actually, the game will track individual NPC ships. What might work is to enable those NPCs to make decisions, then just assume that a hundred thousand other guys made more or less the same decision and do part of the simulation that way. – Schilcote Mar 31 '13 at 23:23

Although this may seem like a bit of a cop-out, it is worthwhile to note that no one can make a provably accurate model of space-faring economics because we have no examples of it in real-life.

All examples of space-oriented trading simulations make their own science fiction assumptions about how their universe works, and most of them take the Planet of Hats approach to alien worlds, in that, despite planets being huge and diverse things, the worlds are culturally very small and limited and possess only one real identity. With this kind of view on planets, it is consistent for them to have only a single, simplified economy for each of them - however, this is certainly a massive simplification of what might occur in real-life.

In other words, if you want realism as your primary goal, then you should know that it is unlikely that there has ever been (at least that I'm aware of) an economic model that is even close to being both realistic and on the galactic scale. Although it may be useful to use real-world economic models as a starting point, there is no guarantee that it will be even close to accurate. There is a measure of fiction, imagination, and utter guesswork that is simply required to make this work.

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There is nothing fundamentally different between "space economy" and regular old economy. Both have transport time and costs, production and consumption, all that. You just have to take into account the details that most earthly economic discussions ignore, which make you think that they're different - unless you've actually studied economics and logistics. – Patrick Hughes Mar 31 '13 at 16:39

I have played a mobile game called Galaxy on Fire, where you would be a space pilot. You were supposed to travel between solar systems each containing 6~ space stations orbiting planets. Each station had its own shop, with its specialities, beverages and whatever you might think of.

Here is the Galaxy on fire 2 Galaxy Map. Taken from the GOF Wikia

The market would be reset every few space travels. With various commodities added randomly. In the top left corner of the map. There has been the most remote station Talidor. Lets say, it has been the only place where you can buy the "Talidor Tonic", it's price would be approx 2k in that station. The approximation would be completely random (I think FishLabs made it +-7% of the initial item value) to give the player a feeling of reality. The Tonic's price is highest in the other corner of the galaxy on Ni'mrodd 9 solar systems away. Where the price would be much higher, Lets say, for instance 190% of the initial cost making you earn 1800 credits from each Tonic you sell. If I were to set up that system I would make one, or more "production" sites, and the further you travel the more +X percents you will get to the items value.

Talidor: 2000; Ginouya: 2200; Eanya: 2400; (...) Nimrodd/Meenkk: 3800

If you feel strong, you can also make more "production sites" which would change the items value using the simple arithmetic mean, using the same method as before "The more times you have to travel, the more the price will rise".

All the values, along with the % the item will rise every time you move up the map can be reset every few travels.

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