In my undergrad, I had the insane idea of hopping into a 3rd year economics course with no prior knowledge of the subject. That course was called “Game Theory”, and (perhaps apart from “Introductory Apiculture”) that course was one of the highlights of my physics degree. Now that I’m in a field that deals with real people, I’m suddenly finding the insights from the course not just neat, but *applicable*. I’ve decided to try and assemble some interesting conclusions, fallacies, and lessons from game theory and their applicability to transit, at least as far as I’ve experienced. This will be the first installment of what I hope is a multi-post collection.

## What Is Game Theory?

Game theory is a mathematical study of strategic decision making, and is one of those wonderful disciplines that lies somewhere in the economic-mathematical-psychology-sociology spectrum. Game theory has seen applications in quantum physics, biology, computer science, and engineering. Long story short, game theory is an attempt at converting human decision making into a mathematical formula, just as transport modeling attempts to convert human-controlled movements into a mathematical formula.

Game theory manifests itself in the form of (you guessed it) *games*, which usually revolve around some number of hypothetical decisions makers (called players) having to make a choice. Their choices can affect others, they can share information (perfect information) or they can be kept blind (imperfect information). Usually, an attempt is made to figure out whether there is some “default strategy” that players will choose (often in the form of a *Nash equilibrium*) if the game is played over and over, with the usual problematic economics caveat that *each individual will rationally chose what benefits them most, given the information they have.*

If that all sounds abstract, it’s because it is. It’s a mathematical abstraction of human behavior, and it’s bound to sound a little silly or problematic. But, just like my transit modeling, game theory is rooted in logic and common sense. That, for me, is enough to make me give it the time of day. I hope to be able to elaborate on some of the terms I just introduced, but it will be done over multiple posts, in what I hope are bite-sized pieces.

While I elaborate on some game theory concepts, just keep in mind the following: a number of *players* are playing a *game, *and they are *in it to win it*.

## The Tyranny of Small Decisions

Broadly speaking, the Tyranny of Small Decisions covers situations in game theory where a number of small decisions, each rational in their own right, leads to a large, overall poor result. Often, this stems from individuals making decisions (say, travel plans) which are essentially spontaneous in time, while larger organizations (say, transit organizations) are affected by long term trends and consequences. The real trouble with this is that for a small decision, *choosing A over B also includes with it a vote for eliminating the possibility of B in the future*. This is an effect that most people do not consider when making small choices about their everyday lives, and why should they? It’s exhausting enough having to make all the choices we already do. Even if by choosing to drive over biking/transit we are increasing congestion (further worsening transit service) and end up stuck in a congested traffic problem, we cannot go back without some sort of cooperative effort to improve transit in one big push. This leads to another, famous game theory example called the *prisoner’s dilemma* which I will explore in another post.

One way to deal with this problem involves a little bit of magic called *foresight*. It requires understanding that this problem exists, and allocating resources to counteract the potential devastating effect of eliminating option *B*. Funding for transit *ahead* of people making these small decisions can move people away from driving and towards transit, and allow us to settle on a equilibrium that is much better than the congested mess we may have been heading to before. This can lead to the problem of free/forced riders, but that is *another* topic for another post.

Another way to try and counter the tyranny is to inform individuals as much as possible about the potential consequences of their actions. If every time you chose to drive you understood that you were potentially helping the demise of public transit in your city, you would be able to make a better decision about your travel, or at least be more aware and accepting of the state of transit in your city. As I said, though, this is probably not the kind of burden you want to bear when deciding how you’re going to get your groceries.

One prime example of a good place to present individuals with a large bundle of options and long-term ideals is during an election (in theory). This is a way for individuals to really step back, look at the long term picture, and *consciously choose A over B in a permanent way.* As important as that sounds, I’ll say nothing more about elections, because this isn’t a political blog, this is a transit blog.

## Vote With Your Feet

Most of my recent posts have been about shifting the way we think about transit, since that is probably the most universally digestible stuff I have to say about it. I hope by introducing a bit of game theory into the conversation I’m able to include a bit of math and logic in a way that’s fun for the whole family. So next time you have a choice about your mode of transportation, remember: **you’re voting with your transportation choices, every day.**