How To Read This Chart: Santa’s wild ride, visualized ~ INFO IMAGES

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By Philip Bump

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Merry Christmas, to those of you who both celebrate and are reading this on Christmas. For those who celebrate and are reading this after Christmas, I hope yours was enjoyable. For those who don't celebrate and who are reading this on Christmas, thank you for taking time on your regular old Saturday to read this email. For those of you who don't celebrate and who aren't reading this on Christmas: Hey, how's it going?

With those formalities out of the way, let's talk about Santa Claus.

One of my favorite bits of data analysis that I've ever done was published in 2019. The premise was simple: If Santa Claus were real and actually had to deliver presents to every kid celebrating Christmas, what would that entail? How many kids are we talking about? How many households? How long would it take?

This involves a more complex set of calculations than you might at first assume. You need to make certain assumptions: At what age does a kid stop getting presents from Santa? And: How many kids within the recipient age range are there? And: How many of them are Christian? You can read the article to learn all of the details, but by comparing CIA (yes, that CIA) data on population and religion (and after weeding out religions that don't celebrate on Dec. 25, giving Santa more time), I was able to create the graphic below, showing the density of targeted kids by latitude and longitude.

At first, this just looks like a map of population density — until you notice details like that Turkey, largely Muslim, is empty. The countries with the most Christian kids are identified (the United States and Brazil) as is the country with the highest density of kids (Monaco). The color scale here doesn't convey the density of kids terribly well; China isn't heavily Christian but has a lot of kids so it looks like a denser target area than it actually is.

In total, Santa needed to visit about 537 million kids in 2019, living in about 396 million households.

Then we get to the mechanics of his doing so. Santa actually has more than 24 hours to get the job done, given that he can start at nightfall, traverse the world and then finish before sunrise. (It is useful for Santa that Christmas is in the Northern Hemisphere's winter.) Because of the movement of the sun, he travels from east to west, covering the United States near the end of the night. But children are not evenly distributed along his path, so he has to rush through the Western Pacific region and Australia to cover the Philippines, India and China so he has more time when he gets to Eastern Europe and Africa.

Or, put visually: here's the density of kids by longitude and the range of north-to-south territory Santa needs to cover. Would be useful for him to being able to travel in a straight line, but he needs to hit Scandinavia and South Africa in the same nighttime hours.

There are a functionally infinite number of ways in which he can hop from house to house, too many for any non-magical entity to calculate. But if we simply assume that each house is, on average, one mile from the next, he needs to cover 396 million miles in just over 35 hours. Or, he needs to travel at 11.2 million mph just to get from house to house, not counting the time it takes to hop down the chimney, drop off a present and eat a cookie.

And yet he does it. And you thought your job was hard.

What is going on here?

Welcome to the inaugural installment of What is going on here?, a section of this newsletter in which we consider some of the world's not-so-great visualizations of data. In a perfect world, this section doesn't exist, as no one would make a misleading or inscrutable chart. But ours is a flawed world, in places deeply and including, at times, in the creation of graphs and charts. So here we go.

We begin with a domain for which data visualizations are tricky. Television is a visual medium in which it's difficult to convey as much information as you would in a short written article, with the obvious exception of video segments. It's what makes cable-news panels odd; they are particularly information-light even when the panelists are adept. It's also a transitory medium, meaning that showing graphs and charts on air is also limited by the need for simplicity. If a viewer can't figure out what she's looking at within a second or two, there's not much point in showing it.

And then, of course, there are those on cable news who are broadly indifferent to sharing accurate information in a viewer-friendly way. People like Fox News's Tucker Carlson.

Earlier this month, Carlson ran a segment focused on the decline of men in the workforce. To bolster his point, part of his broader effort to cast American men as endlessly embattled — "The thing about men is they kind of need to work," he said in the segment — he showed graphs of the labor force participation rate by gender. (That's the percentage of working-age Americans who are working or looking for work.)

Here, as reported by the Daily Beast, is what Carlson showed.

Man line go down; woman line go up. Done and done. Cable news success.

Yet there are two big problems here. The more immediate is that the vertical axis on the female participation rate graph is mislabeled. It doesn't range from 65 to 90 since the labor force participation rate for women has never been higher than 60.3 percent. It's not really clear what happened here. Notice that the grid lines don't actually line up with the axis labels anyway. It's just a mess.

But that leads to the bigger problem. The labor force participation rate for men has always been higher than that of women. Here are the same data, with two changes: a vertical axis that runs from 0 to 100 and both measures shown at once. There is still a long-term decline in the participation rate for men — but also for women over the past decade or so.

Does this reinforce Carlson's point? Well, a viewer encountering this graph might certainly be expected to come to a different conclusion than the one Carlson was intending.

I'm sure he's quite embarrassed by the mistake and will attend to making his points more accurately in the future. Just as I'm sure that there is a Santa Claus.