Now, with the definitions out of the way, we can get to some information. We’ll begin with the most basic measurement: people’s economic and social values. Because our data set is so comprehensive, we can even measure the change in these values with age.

If these lines were of a single person’s lifespan, they’d contain a neat little story:

Both socially and economically, teenagers prefer an anything-goes type situation.

prefer an anything-goes type situation. But as these teenagers grow up a bit and enter the job market , they quickly develop progressive economic ideas: perhaps a bit of “levelling” seems pretty good when you’re staring up the professional ladder from the bottom rung. Meanwhile, their youthful live-and-let-live social philosophy begins to fade.

, they quickly develop progressive economic ideas: perhaps a bit of “levelling” seems pretty good when you’re staring up the professional ladder from the bottom rung. Meanwhile, their youthful live-and-let-live social philosophy begins to fade. In their late 20s , they start making real money. Economic progressivism goes out the window, preferably out the window of a building with a doorman. As the adult mind turns to more material matters, social views don’t change that much.

, they start making real money. Economic progressivism goes out the window, preferably out the window of a building with a doorman. As the adult mind turns to more material matters, social views don’t change that much. Finally, after the mid-40s, retirement looms. Our former teenagers check their collective 401(k)s and think, you know what, let’s all get checks from the government. Social views take a hard turn for the more restrictive. At the end of the journey, economic and social views are again in agreement — only this time on the other side of the philosophical line!

We realize we’re taking a bit of poetic license with this stuff, but the above sketch still illustrates generational differences very well.

Either way, the numbers really come alive when we take a more solid intellectual step and plot social and economic beliefs together as an ordered pair. So doing, we can get a picture of how a person’s total political outlook relates to his age.

With the above plot in hand, we can go even further with our data. The American two-party system creates an interesting mathematical situation: we can bisect our political planea two-party system allows us to bisect the political plane and see which party more closely reflects a given age group’s ideology simply by asking which side of the line the group lands on. People sitting in the upper right half should vote, in theory, for Democrats. People in the lower left, for Republicans. Like so:

The Implication of Our Two-Party System

But of course this line assumes that social and economic values are equally important to a person and that his priorities don’t change as he gets older. Obviously, neither is the case in real life. So let’s see exactly how those political priorities change with age and do even more with our graph.

Digging deeper into OkCupid’s matching database, we find the following new information on people’s political priorities:

A change in political priorities causes our dividing line to rotate

The way this data bears on our political plane is mathematically cool, but arctan(x) really has no place in a political discussion (except in Flatland!), so we’ll just summarize by saying a shift towards either social or economic issues causes our Democrat/Republican dividing line to rotate about the center of our political plane. Here’s exactly how it happens; this chart is basically the sum of all the information we have shown so far. Use the slider to step through the people’s ages.

The Effects Of Changing Political Priorities

From this animation, we can consolidate all that we’ve learned about each group into a single plot. The blue dots are the ages likely to vote Democratic, the red are the Republican ones. In case you’re keeping score, there are 21 blue dots and 22 red ones.

People’s Ultimate Political Tendencies

This detailed portrait of the electorate jives well with the actual exit poll numbers from the last few Presidential elections. The New York Times has collected this data and present it very well, if you have time to take a look. Here’s the part that concerns us:

To wind up this section, let’s take one last look at our political plane, with a final set of overlays that are most illuminating:

The polygons drawn over the dots are called convex hulls; they are a geometric way to measure the spread of a set of points. In this case, the hulls tell us the size of the ideological/age base of our political party.

As you can see, the Democrat’s base is much larger. And the range of political values it encompasses is vast. Here’s party-to-party comparison in tablet form, for easy digestion:

Unlike in many things, size here is a liability. Yes, a political party that’s this wide-open is probably a more intellectually stimulating organization to be a part of, and it has a lot more potential power. But bigger base is also just that many more competing viewpoints Democratic politicians must cater to and that many more different viewpoints in play among the actual elected officials themselves.

Ideological size is a liability

Also, well over half of the Democratic party’s hull lies outside of its upper-right-hand ideological home, implying that you’ve got many groups of people who might tend Democratic, but who have disagreements with the party on particular issues and could defect, should the slant of the party or the country tilt a certain way. On the other hand, the Republicans are concentrated in the lower-left-hand corner. This red cluster has multiple, apparently self-reinforcing, reasons to vote with their party, giving the Republicans both a more fervent power base and a little more ideological wiggle-room along either the social or economic axis.