Can Math Help Repair Democracy? | Sam Wang | TED

45,605 views ・ 2024-09-20

TED


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Computer simulations are everywhere.
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If you navigated here today or you looked at a weather report,
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then you used simulations.
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A simulation can game through thousands or even millions of possibilities.
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What if computer simulations could help us out
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of one of the most pressing problems of our time:
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a rickety democracy, here in the United States
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or around the world?
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I'm here to argue today
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that simulations can help us preserve democracy in a time of crisis,
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in a time of rapid change,
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both technological and demographic and indeed climate change,
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and tension, again in the US and around the world.
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I'm a computational neuroscientist,
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and I'm used to handling complex data.
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My students and I study the brain, a highly complex object.
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We take data and we make it simpler in order to understand it.
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We also build models to help understand how a brain might react.
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And this kind of understanding, I argue,
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is useful in understanding democracy itself.
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Imagine neurons, which I do a fair bit.
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When neurons fire together in synchrony,
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and they fire impulses together,
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that can lead to a seizure.
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Now imagine people doing something together.
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When people start believing something in unison or acting in unison,
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that can lead to political collapse, and it can lead to unrest,
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and it can even lead to insurrection.
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Computation and mathematical analysis
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can help explain strange phenomena like this,
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which are unfamiliar to most of us in our lifetimes.
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They can not only help explain
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but they can also help prevent such events from happening
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and maybe even help make repairs to democracy.
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And finally, and this is important,
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avoid accidentally causing a problem or making things worse.
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I would argue, too,
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that democracy ought to have several fundamental functions.
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It should be representative of all of us.
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It should be responsive to us.
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If we change our minds, we should be able to get rid of the people
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who we think have not been doing a good job.
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And finally, democracy should be deliberative.
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We should elect people who represent us,
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who deliberate with one another and help solve our problems.
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But there's a paradox in our democracy as it stands today.
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And let me explain to you exactly how that paradox might cause a problem.
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If you look at recent surveys,
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many of us are dissatisfied with politics.
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There are more independents
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than either Democrats or Republicans.
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That started two decades ago.
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Over the last few years,
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there are now nearly half of voters in the United States
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who call themselves independents.
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That's more than Democrats and Republicans combined.
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But yet we're also polarized.
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Those independents also have highly reliable voting habits,
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voting with either major political party most of the time.
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So how can that be?
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Let me show you a simple simulation
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that illustrates how both of those things can be true:
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independents who are disaffected and yet partisan polarization.
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And this helps to illustrate
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how there could be a danger to our system under current conditions.
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In this simulation,
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look at this axis from left to right.
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This is an axis that's meant to represent liberals and conservatives
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from left to right.
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And you can see here voters,
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or if you can imagine, politicians, piled up in two great mountains.
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And these two great mountains are separated from each other.
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Very little overlap in issues or in cultural stances.
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There's something different about these two mountains.
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But now take a closer look.
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This is one dimension that I've shown you,
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a single dimension from left to right.
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But look, here's a third mountain hidden.
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And that's because there's more dimensionality to voters
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than just the single axis
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that we've gotten used to in the last few years.
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This third mountain of voters, in fact, has different stances,
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but yet they're forced to choose.
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They have to pick whichever major mountain is next to them,
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and whichever mountain is closer, they pick.
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And that's why we're loyal.
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And when we're forced to choose between these two major mountains,
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we're all forced to act as if we're on that single dimension.
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Mathematical analysis has shown that one-dimensional dynamics,
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as you go along a single dimension, can lead to instability.
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And that's important.
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To get into the math a little bit, imagine animals.
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If animals all start moving in one direction,
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then that puts them at risk of getting into a stampede.
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Now imagine people.
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If we all start doing the same thing,
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if we all start behaving in unison, if enough of us do that,
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that can cause a political stampede.
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And a political stampede can lead to the election of extreme leaders,
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and it can lead to a collapse of democracy and maybe the loss of democracy
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and future elections.
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Can we prevent this?
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Well, I should say that reformers have come up with lots of ideas.
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And if you've been paying attention to this space,
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you've heard about some of these ideas.
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But the problem is that we do not have the luxury of time.
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It's an unstable time.
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And I would say that it would be a good idea for us
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to make some of these repairs in the next few years.
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And we have to get it right maybe the first time.
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Simulation can help.
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Like navigation on a smartphone,
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computation can help us identify paths that can move us forward reliably
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and without making too many missteps.
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Now I’ve told you about independents.
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Now I want to tell you about some of the solutions.
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Now you might imagine that a good idea in such polarized circumstances
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is to form a third party.
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Sounds good, right?
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But in fact, if we do that before attempting other reforms,
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that can backfire.
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And I'd like to show you a simulation that proves the point.
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Here's a simulation based on analysis
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that my collaborators and I have undertaken.
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This is now based on results from analyzing hundreds of elections.
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And we found that voters indeed do act
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as if they are piled up into two great mountains.
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In this case, I’ve shown the blues on the left
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and the reds on the right.
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And in this simulation, they vote under the normal rule
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that we’ve become used to, which is called first-past-the-post.
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And in this simulation I've set up conditions
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so that out of 10,000 simulations, the blues win half the time, 5,000 times,
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and the reds win half the time, 5,000 times.
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And in the simulation, the fraction of the vote
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that they need in order to win is about 50 percent.
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These are the conditions that we're used to in a two-party system.
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Imagine if we suddenly run a third-party candidate
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and we put that third-party candidate in the middle.
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The third-party candidate is here in the middle,
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and I've set up the simulation to be a little bit closer
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to one of those peaks than the other,
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because that third party is more sympathetic to those views.
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However, there's something a little bit funny here,
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which is that now that blue party
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still needs 50 percent of the vote to win.
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But now, because the third party has divided the vote,
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now the reds only need 46 percent of the vote to win.
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And now we have a situation in which out of 10,000 simulations,
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the blues win now only 2,000 times, the reds win 8,000 times,
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and the third party doesn’t win at all.
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And so this is counterproductive, right?
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This is what we call a spoiler effect, where paradoxically,
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the third party has spoiled the chances of the party that is closer to them,
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which is presumably the opposite of what they were trying to accomplish.
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Now there are other solutions that it turns out are more likely to work.
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And one of them is redistricting.
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In the United States,
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we're mostly represented in single-member districts,
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and so we have a particular legislator who represents us.
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In recent years, there's been a move to stem this.
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You may have heard the word gerrymandering.
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Gerrymandering is the artful drawing of lines
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to disadvantage one candidate or a group,
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could be a racial group or a whole political party,
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and to eliminate competition.
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Computation can help identify such a plan.
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By doing statistical analysis of the universe of possible plans,
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it’s possible to show that a particular plan is an outlier.
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And when there’s an outlier, then a court can intervene.
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When the court intervenes, it can dictate the drawing of a new plan.
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Computation can also help voters.
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Voters who vote to change the system, to change the rules,
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to establish an independent commission,
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can also take the power away from legislators,
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and they again will need computation.
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However, this solution, as attractive as it is, is not enough.
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And that's because those two mountains which I showed you are everywhere.
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And no matter how much we redraw the lines,
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there's polarization across the nation.
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And so the question is, OK, what else do we need to do?
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There's something else that's necessary.
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The next step is to change the rules of the game itself.
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Alaska voters in the last few years have done exactly that.
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They voted to do away with partisan primaries.
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What they've done is remove the primaries
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and replace them with an all-party primary.
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Everybody runs in one single primary.
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The top four advance to the general election.
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Because there are four candidates,
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they then have to be elected under a ranked-choice rule.
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Ranked choice is one where you list your first choice, second choice,
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third choice, fourth choice.
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If your first choice doesn't cut the mustard,
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then they drop out, and your vote is reassigned.
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The consequence of this is that Democrats and Republicans
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still have a chance to advance, and they do, to the general election.
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But it changes the incentives.
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They have to play not to their party faithful
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but instead they play to all voters.
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It changes tactics.
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They try to win over each other's supporters,
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and it changes attitudes.
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And just to give you an example,
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here's a selfie that's taken by three congressional candidates,
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one Democrat and two Republicans.
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And here they are chumming it up, taking a selfie together.
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And I can tell you that at least one of these candidates
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is not in the habit of chumming around with a member of the other party.
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(Laughter)
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So this is one way that, in fact, a new change of rules can help.
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And in fact, we've done simulations that show that this rule,
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which is called top four primary, works with redistricting reform,
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the other one I showed you.
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Put together, they can, in fact,
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double the number of competitive districts.
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So there's even a case in which there's synergy that's possible.
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Now I’ve given you a few ideas,
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but there are actually many ideas for reform and you may know them:
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eliminating the Electoral College,
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approval voting, campaign finance reform.
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The question is how to choose
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and how to figure out which ones to do first
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and with the most urgency.
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And simulations can again help.
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Simulations can game out outcomes.
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Representation, responsiveness, deliberation.
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And simulations can do something
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that enacting a reform cannot do easily,
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which is game out long-term outcomes.
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What’s going to happen 10 years from now?
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And that's important.
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Furthermore, every state is different, cities are different.
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The same solution is not going to work in every place.
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And so it's important to be flexible
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and to look for the solution that works best.
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Somewhat shockingly, some states have even outlawed ranked-choice voting,
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and so one would have to come up with another solution for those places.
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Now let me be realistic.
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Math is not enough.
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But math can be assistive,
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and it can help speed the process for people who want to change the system.
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In other words, math and computation can act as a GPS
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to rescue our lost democracy.
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Now the way you can help is by advocating for reforms
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through voter initiatives in states that have that.
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You can advocate for local reform in your city or town.
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And if you're a scientist, I really want your help.
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If you're a scientist, I want you to come
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and get to work understanding these things
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in your city, in your town, in your state and in your nation.
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As it turns out, some of these reforms, such as ranked-choice voting,
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have been run in hundreds of elections across America.
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And that means there are experiments being done right now in real time.
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I want to end with a quote from a former president, Theodore Roosevelt,
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who was not a scientist, but in fact was very interested in this.
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And he called democracy an experiment.
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He said, "Democracy is this national experiment
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in which it's essential for the rules to end up representing all of us."
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It's my hope that math can help get us there
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and build a better future for all of us.
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Thank you.
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(Applause)
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