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.” 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?