Tuesday, 1 November 2016

The NYT election map

It's election time in the US. It has been for well over a year (which is madness in itself) but we're down to the wire now with only a week to go before polling in what must be one of the most hate-fueled, vitriolic contests ever. Lies and misinformation have taken centre-stage but the sad truth is there are people (people who vote) who are easily taken in by lies and misinformation. They are sold it as a version of the 'truth' they can relate to and in which they wholeheartedly believe. And so that's how propaganda becomes reality and how candidates gain disciples. It's often the same with maps because they too sell a version of the truth.

We're arguably on the cusp of something far more important than worrying about a map in a newspaper but to my mind, at least, today's HUGE map in the New York Times warrants some cartonerd attention.

It is a truly magnificent piece of work. Large format. Eye-catching. Detailed. The US is a big country so if you want to show 30,000+ zip codes you better make your map big. I am a huge admirer of the New York Times graphics team and their cartographic work but this map, I'm afraid, contributes to the misinformation that has become so toxic this election season. Let's not worry about the periphery because it's the main map that takes centre-stage. It's that image which is defining and the impression that people see.

So what do they see? RED...lots of red. Any map that attempts to summarise a sparsely populated data set into a surface that exhausts space will mislead. It's inevitable. And with the USA, with a very heterogenous population distribution and vast swathes of land with barely a single rattlesnake of voting age it's a problem that is accentuated. The map uses Zip Code Tabulation Areas instead of counties, voting precincts or other geographies. There are problems with how ZCTAs mis-shapes the view but, frankly, any arbitrary boundaries have the same problems - the Modifiable Areal Unit Problem - statistical (and ultimately visual) bias that results with how you aggregate data into areas. The geography is what it is...but rather than perpetuate visually incongruous issues it's beholden on map-makers to deal with it.

For the last few years in my day job I've given a workshop at the Esri International User Conference that takes a single dataset of the 2012 election results and explores a range of about 20 different ways to present the very same data - each of which tells a very different story. Some of the maps can clearly be used to portray a particular dimension of the result and some can be used in deplorable ways (pun intended). Some reveal detail. Some mask it. Some show red. Some blue. You can see the full range of maps here if you're interested. The point of the session is to open people's eyes to the inherent biases that maps contain. What surprises me year on year is that an audience of people heavily invested in geo are equally surprised at the problems we explore. I guess it's to be expected - not every geo-expert is going to be a cartographic expert and they come to the session to learn and that's a great thing. But they are merely a small fraction of the population. The vast majority have no access to this sort of education. More than that - they have no idea they might even benefit from it or that there's a problem with how they read the maps they are served.

It's really a much bigger problem of geographical illiteracy and the lack of the basic need to view maps and graphics critically. With all these much larger issues it therefore becomes crucial for media organisations and those involved in communicating information to be cognisant of the limitations of the consumer. It's not really their fault - we're all born that way and we have a natural tendency to believe what we see, especially if it comes from a so-called reputable, impartial source. Maps should portray reality in a way that deals with the biases people inevitably see - to counter them rather than feed them. You only have to read the comments in reply to the NYT tweet to see how the map has been viewed and interpreted.

The problem with this New York Times map is the country itself which, admittedly, there isn't much they can do about but they could deal with the problem using different maps.  The size of the areas used to summarise the data are unequal. Some are therefore more visually prominent than others. Republicans hold on to large swathes of centrally located territory. Democrats get a shed-load of votes from the smaller, peripheral northeast. Additionally, they contain very different numbers of people so population density is unequal across the map - yet in terms of the symbology, each area is treated the same.

So you end up with large swathes of sparsely populated large areas in the mid-west being seen prominently and very small, densely populated areas on the coasts being seen much less prominently. The problem is compounded by two other factors - colour and focus. Red for republican is a colour that is seen more brightly than blue for Democrat. It is cognitively processed as 'more important'. Our eyes also naturally tend towards the centre of an image and a map on first inspection - so that's our initial focus. this all adds up to one massively misleading picture of the political geography of the USA. It screams REPUBLICAN which given Trump's persistent comments about the corrupt media is either an attempt for NYT to redress the balance or the Russians are to blame. And yellow for the marginal areas? I understand the desire for a neutral colour but in a generally two-horse race (mule, elephant, whatever) adding in other colours paints a different picture as well.

It can be different as these following maps of the 2012 election results, mapped by county, show. Using a value-by-alpha approach that overlays a layer of population density that is symbolised so that sparsely populated areas are more opaque will modify the image. It tunes out sparsely populated areas and brings a little focus to the areas with more people (more voters). All that deep red on the NYT version has now gone. Focus is shifted.

A cartogram does a similar job but by changing the shape of the areas - either warping them in relation to population density (e.g. a population equalising cartogram) or by giving each unit area the same shape (e.g. a hexagon grid). Yes, these are abstract and there's sometimes a challenge understanding the geography but they deal with the problems.

There's even the simple, yet effective, proportional symbol map that often gets overlooked. Symbol overlaps are often hard to reconcile but the symbol sizes do a good job of showing where there is more and where there is less as well as encoding the different colours.

Finally in this small selection of the myriad of alternatives, a dasymetric technique which uses a secondary layer of data into which you can reapportion the data can also show a more accurate distribution of information (e.g. dasymetric dot density) though, of course, any map of population data presented in this way will take on a similar appearance because, well, that's where people live!

Ultimately, there are dozens of different ways that the map can be made. None are 'right' and none are 'wrong' but they all tell different versions of the truth. This isn't cartographic pedantry. It's an important issue because it plays to people's views, opinions and search for the truth. My point here, is that maps can be extremely dangerous graphic tools. The NYT have, in my opinion, contributed to the misinformation that has enveloped this election by publishing this map in the form they chose. It presents a version of the truth that suits a particular view of reality. It is biased and dangerous. It's also too late because it's out there now and is simply just another piece of rhetoric people can use to support their own version of the facts.

By the way, I don't get to vote in the US election but I have lived and worked in the US for 5 years and call it home. Please...do yourselves a favour and go vote. You only have to look at what happened in the UK a few months ago where the vote was to leave Europe...a vote massively impacted because many people failed to turn out to vote who would otherwise have voted not to leave. You can't vote by liking or re-tweeting. Whatever the map says to you...just go and vote and help redraw the one you want.

UPDATE: Since writing this less than an hour ago the Washington Post has published a very well-timed piece entitled Election maps are telling you big lies about small things. They've been advocating cartograms based on one area per electoral college vote which I like. It retains a State-based appearance (which isn't as difficult to read as the population equalising versions) while doing a good job of presenting a visually balanced view of the data. I encourage you to read.

UPDATE 2: And now a good review of past approaches from NYT here. A rebuttal of the criticism they've faced? Maybe. They try and frame the big map as an attempt to look at the way physical geography impacts political patterns. That's a very nuanced way to explore the distribution of voting and I'd still argue that most who read the map will take away one message...more red = more Republican. Seven days out from the election is not the time to be playing with people's inherent perceptual and cognitive bias.

Monday, 3 October 2016

Brewdog: Stick to the Beer

I've written about non-normalized choropleths before (e.g. here and here and here) but when one of my favourite breweries makes the mistake I feel compelled to mention it again.

Brewdog are setting up in the USA. This is a good thing because their beer is spectacularly good. I have become an investor in their USA Equity for Punks campaign to support their efforts. But they need a cartographer because their maps are spectacularly bad.  They've been running this map showing how investors are spread across the US.

Clearly they're mapping totals as a choropleth which as most who know me will know gets me really rather upset. I mentioned this to Brewdog but their reply suggest (a) they don't get it and (b) they don't care.

Yes, I get that it's a bit of a fun but that's not actually a good excuse for making a crap map.  I could make some shitty home brew just for fun as well but what's the point of that? I'd rather try and do the job right and make something that tastes good. They've also used a poor blue to red colour scheme but that's a different argument. Anyway, I have offered to help them correct it so just because I can, here's a couple of efforts whipped up in less than an hour.

Here's the (incorrect) totals version as a choropleth in Punk IPA colours:

And here's the same data of the number of investors, normalized by the number of people over 21 (drinking age) in each State to create a 'Punks per Million' map. I guessed on roughly what the data might be from their original map:

Compare thee two maps. You see - because the population of each state differs massively and the size of States differs massively, using totals inevitably skews the map numerically and visually and you get a warped sense of reality. Texas will always come out as a lot. Montana always not. But actually, as a proportion of the population, there are more Punk investors in Montana than Texas. Ohio still gets shown as having the most investors because they have a lot (as totals) and as a proportion of their population and that's where the new brewery is. But California isn't a stand-out because it has roughly the same Punks per million as Oregon and even Wyoming.

Still want to map totals? Well use a proportional symbol map:

There you go - now you can clearly see the huge difference in the pattern of investment between states. And if you want to Punk out the map...well go right ahead:

And yes, I used the same bottletop technique on this quick map as I did on the much larger Breweries of the World map which, if you want a copy, can be downloaded here.

So, Brewdog. I like your beer a lot. You take great care to make it right. I like maps a lot and I take great care to make them right. You stick to brewing and I'll keep drinking your beer. I'll stick to making maps. If you want some help with the maps, just drop me a line.

Wednesday, 20 July 2016

Taste the rainbow - third helpings

If I'm going to have a carto-argument I may as well have it with the President of the United States.

Today, President Obama used this tweet to encourage us to be aware of rising temperatures and the need to stay safe and watch out for others. I have no qualms with the intent but as you'll appreciate, the cartonerd in me got quite irked by the leading statement.

"This map says it all". Well despite rainbow colour schemes being used to death to map anything and despite people preferring their own facts and telling me everyone understands the scheme I resolutely beg to differ.

I wrote about this problem several times before herehere and here. And so have others here, here and here. Rainbow colour schemes do not work well for numerical data where the analytical task is to determine what is higher and what is lower across the map.

Put simply, our brains do not process colour (strictly speaking hue) in a way that tells us a quantitative difference between them. Different hues (yellow, red, blue etc) work very well for showing qualitative differences on a map. Single hues, that vary from light to dark, or even a dichromatic scheme that blends a couple of colours do a much better job at encoding a quantitative difference.

In the map above, there's no logical consistency in the brightness of the colours. Some stand out more than others. Magenta is arguably the colour we see as the brightest yet there's a sort of light cream colour in there that actually means 'more'...and that's before we get to yellow. Yellow is not 40 degrees hotter than cyan on the spectrum either. Rainbow schemes are not perceptually uniform, they modify meaning beyond what the data supports and create visually false boundaries. You could also easily reverse the scheme and it'd make just as much sense.

The argument that people understand it is borne out of the simple fact they see them every day so they believe they understand them. They're conditioned to them. It's called brainwashing. I get it, We're all liable to a bit of brainwashing from time to time and just because you relate hot with red and cold with blue then it's all good OK?

Well no...because on this map yellow, magenta, a light pink and burgundy is hotter than red which happens to be in the middle of the spectrum. And how hot is green exactly? I've never been green-hot. I would still argue vehemently that without a legend these sort of maps are harder to interpret than they need to be.

Given in every other aspect of life people seem to want the easiest, laziest path of least resistance to something, why they force their brains to interpret rainbows baffles me. More so, the arrogance of constantly using your own facts to contradict cognitive science just shows a complete unwillingness to accept a better way. Hell, rainbow palettes aren't even 508c compliant!

End rainbows! #endtherainbow

Saturday, 16 July 2016

Chip paper silly season

It's likely most will have already forgotten that a few days ago the Wall Street Journal published a short article on Null Island. After all, today's news is tomorrows fish n' chip wrapping.

A couple of months ago a journalist contacted me wanting to chat about this mythical place he'd heard of. I agreed. It was supposed to be background for the piece he was writing but I made it clear I was not qualified to be regarded in any way as an expert or even protagonist for the rise of the Republic of Null Island. We spent well over an hour chatting about basics of cartography, maps and such like. We got into coordinate systems, datums, map projections and so on.

I never got to see a draft of the article but there it was, front page of the Wall Street Journal. In some ways it was a nice piece for a general audience but tucked away was this fantastic quote I'd apparently made: “There is a lot of terrible-terrible-terrible math involved,”. Did I say that?

To be honest I can't recall but the conversation was about the need for different local coordinate systems and because the earth was a geoid (I never said lumpy egg-shape) that involved maths to make flat maps. I am liable to the odd quip but I can't recall saying 'terrible' three times. Maybe I did, but the point I was making was that making maps involves maths and it can get rather complicated whereas the article juxtaposed that alleged quote with something unrelated to what we'd discussed.

By the way, that's maths with an 's' because I speak English English, not American English. I entirely understand the s being dropped as it's a U.S. publication but it did cause amusement among a good number of my geo-pals.

The paragraph then went on to label me a 'Senior Cartographer'. Umm - nope. No such job title at the place I work. The full title of my employer was written out (despite it hardly ever being used these days to my knowledge) and then another alleged quote was appended: “Every part of the planet differs from every other part and that is why we have all these different maps.”

Well...no shit Sherlock! Again, I was actually referring to different coordinate systems as context for that but clearly that was deemed irrelevant.

So what's the problem? Ultimately it's just a media piece. My grand contribution boiled down to two pretty pathetic alleged quotes in an otherwise decent piece.

The bigger problem lies in the fact that so many journalists these days seem hell bent on taking information they gather from numerous sources (often Wikipedia, organisation web sites and LinkedIn) and just pasting it together in a way that they think makes sense. Context is lost. quotes appear uninformed and vapid. And in only a few lines the article managed to make me sound daft, give me a different job, include my employer's details (despite this having nothing to do with my employer) and dumb down the conversation we had to a banal au jus. This has consequences. I get a good ribbing and some eyebrows are raised. For the reader, they take away something only half-formed and that can then propagate. I guess this has always been the case with news media. It's not the first time I've been involved in a piece that ended up less than impressive.

Thankfully I did urge the guy to contact Nathaniel Vaughn Kelso which he obviously did and it can't be a bad thing that he and others get recognition.

And just as I thought things had died down someone on social media posted a link to the article clearly suggesting that I had said Null Island was "a place for people who can't use maps". I never said that. Neither did the article.

Lightweight reportage followed by Chinese whispers (that's the 'telephone game' for U.S. readers).

Silly season has arrived. Anyone fancy a chip?