{"id":473,"date":"2021-03-26T18:49:14","date_gmt":"2021-03-26T18:49:14","guid":{"rendered":"http:\/\/abbymullen.org\/hist390spring2021\/?p=473"},"modified":"2021-03-26T18:49:14","modified_gmt":"2021-03-26T18:49:14","slug":"thinking-about-maps","status":"publish","type":"post","link":"https:\/\/abbymullen.org\/hist390spring2021\/uncategorized\/thinking-about-maps\/","title":{"rendered":"Thinking about Maps"},"content":{"rendered":"\n

Today our topic is one of my favorites: Maps! Ordinarily we\u2019d actually spend two weeks on this topic, so you\u2019re getting the Reader\u2019s Digest Condensed Version today. (Also, if more than one or two of you gets this reference, I\u2019ll be shocked.) If maps interest you, or they interest you more after reading this blog post, you should take another class with me. I love maps and we talk a lot about maps in all my classes.<\/p>\n\n\n\n

Just like with visualizations, these days maps are everywhere. And, just like with visualizations, we\u2019re trained to see maps as being inherently truthful. We think of them as being factual representations of reality. But, again, that\u2019s just not true. Maps are as fallible as any other type of visualization–and in fact, that\u2019s what they are: just a specialized type of visualization. So all the rules we already talked about with reading visualizations still apply.<\/p>\n\n\n\n

Just to review, those are \u201cData, argument, structure, and distractions.\u201d We\u2019re not going to go over all of those again. But I do want to talk about just one form of misdirection that maps are exceptionally good at: representing people as land.\u00a0<\/p>\n\n\n\n

Maps can mislead just like any other visualization.<\/h2>\n\n\n\n

At the risk of getting political, one of the best–or worst–examples of this phenomenon occurred in 2019 when Congress was conducting the impeachment of President Trump. Several officials tweeted out a map that got a huge response from Trump supporters. It was a map of the United States, colored with blue and red, as you\u2019d expect, and the caption was \u201cImpeach this.\u201d This map was, of course, based on the 2016 electoral results. The country was almost entirely red. The argument Trump\u2019s supporters implied was that the red area was so much vaster than the blue area that it would be impossible to get support for impeachment. Aside from the fact that partisan affiliation ought not necessarily map onto support for impeachment, there\u2019s a big problem with that map. The problem is that much of the population of the United States lives in the small blue areas on the map. So the landform of North Dakota or Montana might be red, but the people in New York or LA are blue. <\/p>\n\n\n\n

So this map has misled us by giving us the wrong scale. The scale shouldn\u2019t be the land. It should be the people. <\/p>\n\n\n\n

Here\u2019s a GIF that illustrates how one cartographer solved the problem of counting land instead of people regarding this map. In your group, discuss what he did. How is the map different now, both in look and in argument? (By the way, the map he created is called a \u201ccartogram\u201d because he\u2019s not exactly mapping the space.)<\/p>\n\n\n\n

\"\"\/<\/figure>\n\n\n\n

Ironically, the solution to this map\u2019s problem can create problems for other maps. Sometimes we take the absolute aspects of our numbers at face value, without considering other factors like how the space actually works. Note the XKCD comic here. It\u2019s pointing out a common problem: making claims about how people behave that\u2019s actually just about how many people are present. In maps that make these sorts of claims, we very rarely need to know the absolute numbers (voting numbers aside). Instead, what we want to know is percentage. <\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

XKCD comic about heat maps<\/a>. <\/p>\n\n\n\n

The maps in the XKCD comic are often called \u201cHeat Maps.\u201d But heat maps that account for absolute numbers end up just mapping the population density. What we actually want to know is what percentage of the population fits into these categories, or some other relative metric. If 10 out of 100,000 subscribe to Martha Stewart, it\u2019s maybe not that that remarkable. But if 10 out of 100 do, that\u2019s a much bigger percentage. Maps that rely on absolute numbers can be misleading. So always check the scale and methods, just like for any other visualization.<\/p>\n\n\n\n

What can maps do for me?<\/h2>\n\n\n\n

Why should we care about space? In one sense, it\u2019s obvious: we live and move in a spatial world. Looking at space can help us to understand the scale of things in a way that mere words may not be able to convey.<\/p>\n\n\n\n

But…get ready to be shocked…space isn\u2019t the same for everyone! We all conceive of space in different ways. Just like with time, there are some \u201cstandard\u201d units of space that are commonly used, but not everyone agrees on them or on their value. Go search in the search engine of your choice for \u201cMars Climate Orbiter\u201d to find out what happened when two different groups of people used different units of measurement.<\/p>\n\n\n\n

Not only do we use different ways to measure space than others, we also sometimes draw space differently. It\u2019s all mostly academic if you\u2019re just drawing a map out of general interest. But if you\u2019re drawing a map that\u2019s meant to get someone from point A to point B, like a ship\u2019s navigational chart, you probably want the map and the actual earth to be somewhat similar. This has been a problem since the first days of mapmaking: how do you represent a 3-dimensional object (the earth) in 2 dimensions (a flat piece of paper)?<\/p>\n\n\n\n

Well, I could answer this question for you, but I think I\u2019m going to let the West Wing take this one. Check out the YouTube video<\/a> I\u2019ve linked below.\u00a0<\/p>\n\n\n\n