 The movie A Beautiful Mind with Russell Crowe tells us the story of a mathematician and economist John Nash, who as part of his PhD work in the 50s created something really disruptive to economics, which is a theory which shows that if players work non-cooperatively in a game or process trying to maximize their own profit, they actually end up in a result which is suboptimal called a Nash equilibrium, in which they're not as well off as if they had cooperated. And this is a game that all of us today are playing, because when you go to work, when you go home, you want to get there as fast as you can, and you all use apps that are not playing with each other, whether you use Google, Waze, Inricks or many others, and you're not cooperating. And so of course, why should you? If you think about this, there is no reason why you should spend more time in this rather than being at home or being at work and being productive. And so the story that we're going to tell today is the story of how in ten years we got where we are. Ten years ago, if you were hitting the road to go to work, you had two ways to get traffic information. You could log to 511.org or listen to Joe McConnell on KQED right before Michael's show. And within two years, a project called Mobile Millennium that was launched at the University of California at Berkeley created what you see on the right here, which is essentially traffic for all of you everywhere all the time for free. Except what people didn't think at the time, and of course now everybody has this on their phone, on their apps, what people didn't think at their time is that this is what enables you to play a Nash game. When cities partnered with these companies initially, they thought they were doing something really nice. And in fact, there was no way to know that if more and more people were using the apps, things would get worse. But if you've seen more traffic in your neighborhood recently, you're not alone. This is what's happening every day in California and in the rest of the US. In fact, this has become so bad that residents have themselves identified the cause for their problems. Specific companies or specific services. In fact, some residents have even started to resist by shaming people holding signs, you know, don't go through my neighborhood by posting fake detour signs, you know, so that people would avoid by paying senior citizens to hold a phone in their hand walking along the street pretending their car stuck in traffic so that the algorithms and the learning would learn to avoid their neighborhoods. This is the beginning of the resistance. And it got worse because actually the city started to get involved, building more street bumps, more stop signs, more turn restrictions, to make their own traffic worse. Because how else could you maintain external people from coming to your neighborhood if you make your own life worse? This is the reality of city planning today. And in fact, we see the first lawsuits coming in some places in the world to try to fix this problem. This is an epidemic. This is a disease. It's spreading. These points on the maps show you an example of where we've seen this in the popular media in the last couple of weeks in California. If this is hitting the popular media, that means it's everywhere. If you've seen it, it's you're not alone. And so how can we fix the disease if we don't understand it? And that's the work we do at the University of California at Brooklyn. I'm going to show you a movie which shows the impact of information on traffic. In this movie that you see here, you will see on the top part what happens if a certain percentage of the people have the information, and on the bottom if they don't. There is an accident. It blocks lanes. We see this every day in California on many freeways. That creates congestion. If you have the information, of course, you're going to leave the freeway. So you're going to try to find an alternate route. If you don't have the information, you're going to stay on the freeway. The problem is at some point the accident gets removed because the CHP has done their job really well. And then people who have left the freeway, who have that information, are still leaving the freeway. And what it does is it creates an activation of a bottleneck because, of course, everybody's using the same off-ramp to get off the freeway. So what does it do to the freeway? It congests it even further. And so now you have additional congestion on the freeway where you would not have it had you had not that information. That shows you the impact of that information. The situation then gets much worse because hundreds of people, just like you, want to go on the side streets to use a shortcut, except these were never designed to handle the traffic. So now, in addition to congesting the freeway, you've also congested the side streets, the intersections. They can't handle it. They don't even know about this because they're working on fixed single timing plans. So now in addition to also jamming the side streets, you're also jamming the connectors because the intersections themselves get perturbed by this extra traffic. And in the process of that, you're also now jamming the other direction of the freeway. So you can see with this illustration an impact of the information on traffic. And so this is what we don't want. This is the result of a Nash game. And what we really cannot do is we cannot build ourselves out of congestion. There's no more space to build freeways. So the only way that we're not going to end up all in a Nash game is if we have to learn to play corroboratively. And what that means is all of us being spread on different routes by the apps, if the apps are able to collaborate and if the apps are able to take this into account. And more importantly, we need to enable the collaboration between the private sector and the public sector because at the end of the day, the people receiving the traffic are people who live in the city and their infrastructure of the ones who are able to handle it and have to handle it. So what we do at UC Berkeley to prevent this Nash game from happening every day in our lives in California and the world is develop the proper science and technology so we can enable this collaboration both at the commuter level, you and me and the city level. Thank you.