Wednesday 28 May 2014

Testing..testing...1, 2, 3.

I was reminded this week of a number of ways in which you can assess cartographic work in simple ways. A conversation between Alberto Cairo and Moritz Stefaner trod over some old ground but their conversation is worth exploring because much of what I see fails these simple tests (and leads to me blogging). They debated the first and second of the simple tests I set out below. I added the third. These are tests that I (and many others) apply when looking at and critiquing maps. They are the basic tests that anyone can apply:

So What?
The first test is simple...does the work you are looking at leave you asking so what?. This is how we used to assess student dissertation proposals and get them to reflect on whether their proposal was worth doing. Was it persuasive? Did it make me want to know explore or find something out? Did it make me care? All maps ought to, at some level, inspire their intended audience to want to care about what it is that's being illustrated and the message of the map. It has to have a function and if the form is well crafted that function should be visible. The map may very well have a good purpose to the map-maker but has that been extended to an audience?

This isn't an exact science though. Different people and user groups have different so what thresholds and so what works for one may not necessarily work for another. This is where a consideration of the audience comes in when you are making a map. Engage your audience first. Bring along others if you can. Pleasing everyone all the time is impossible though.

It's also perfectly reasonable to experiment and at the moment we're in a period of cartographic development where technology is out-pacing best practice. Animation and 3D are just two areas that we've always played with but now the tools are mature enough to allow people to really get their hands dirty...and they are. At the moment there's too many failing the so what? test. This may not be a bad thing IF it leads to new ways of working that make good use of the techniques.

Let's assume people have got past the so what moment because, let's face it, if they haven't then they've already clicked to another web page or left dissatisfied with your work. Upon inspection, does the map give you some sort of mini-eureka moment? Is the message communicated with clarity and has the map-maker made it legible? Clarity and legibility are key though they are not the same thing. Clarity relates to the message. Has the message been encoded into the map's syntax effectively. Legibility is the way in which the map-maker has brought focus to that message through effective graphical structure.

Put you get it? This is the ah-ha! moment when you realise what it is you're supposed to learn or find out. It should come relatively easily.

The person that reads your map should leave with a deeper understanding of the theme or topic. They shouldn't have to work too hard to gain that understanding either. The ability of the map-maker to make you care enough to want to look at the map and give you some sort of clarity about a topic is what good cartography is about.

The squint
Does the story of the map immediately jump out at you? Given we cannot rely on people spending that much time or effort viewing your map, making the message legible is crucial and this has a lot to do with your ability to structure your map. This is down to what British geographer William Balchin termed graphicacy. He coined the phrase in a 1972 address to the Geographical Association. Graphicacy is the natural counterpart to other cognitive intelligent processes of communication such as literacy, numeracy and articulacy. Maps and other spatial documents are the tools of graphicacy and the very basis of geography. Cartography is the professional application of expertise in graphicacy.

Becoming proficient in graphicacy will help you tell your story more effectively in the same way that effective writing or speaking skills helps you communicate using the written or spoken word. If you know how to speak in a graphical language then you're half way to being able to communicate your message. This goes beyond knowing constructional techniques and mechanics for knowing how and when to use certain graph or map types though. It's just as much about how you organise them on the page or screen. While written and spoken language comes at us in word after another in a sequence that our eyes follow and our brain systematically decodes, pictures arrive at our eyes in parallel. Maps are presented all at once. So we need to encode them so that certain components appear more prominently to give our brains a chance at decoding into some sense of order. These lead the eye. they may be larger or more visually prominent, they may use lighter or desaturated or bolder or more saturated colour, they may appear in a certain animated sequence or they may require interaction but doing a squint test is a good way to determine whether what you are looking at is communicating well.

So...sit back as if you're in a wild west film, chewing on a cheroot and pretending to be Clint Eastwood. then squint and look at the map. What do you see? If you can still make out the main features and the central topic of the map then chances are it's got its graphical structure well proportioned and balanced. It's a simple way of seeing whether what you are seeing is what your brain is receiving. If your eyes are picking out peripheral or less important components under this test then that's going to cloud the message. There is some science behind this...what you're doing when squinting is reducing the amount of light entering your eye. Your peripheral vision is also impacted. You therefore have lower levels of visual acuity (visual resolution) and so you are trying your hardest to pick out key shapes and features.

And finally...some words from a master
As with everything, there will always be examples that break the rules. there will always be innovation that overrides some of this so be mindful of that when looking at maps. Also, remember that the value of a map is going to vary between audiences so that will undoubtedly affect your impression. Then there's the final matter of subjectivity. While the above are semi-objective tests there's no doubt that we all have preferences for certain types of maps and particular looks and feel. Do you prefer Monet, Turner or Banksy? We all bring our subjective preferences to the table.

In the week that the great designer Massimo Vignelli died it's worth reflecting on some of his basic tenets in design and thoughts on why experts in a field are important in the context of shaping best practice. This gives context to the simple tests described above:

"I like design to be semantically correct, syntactically consistent, and pragmatically understandable. I like it to be visually powerful, intellectually elegant, and above all timeless."

"If you can design one thing, you can design everything."

"I thought that it might be useful to pass some of my professional knowledge around, with the hope of improving [young designers'] design skills. Creativity needs the support of knowledge to be able to perform at its best."

"If you do it right, it will last forever."

"The life of a designer is a life of fight against the ugliness."

"There is no design without discipline. There is no discipline without intelligence."

"Good design lasts longer."

"...and that is why I love Design."

The three tests outlined here are basic things you can do to see if your own designs are working and to look at whether other designs are working. It's not rocket science but it may just help you to take a step back and reflect on the quality of the work. There's lots of fancy ways to make maps but fundamentally...are they working?

Saturday 24 May 2014

LyricMap: Where the Streets Have No Name

Inspired by the nonsense mapping of The Proclaimers 500 miles that I re-mapped, I was pondering a few other geographical lyrics and how they might be mapped. I'm going to call them LyricMaps ™ and there's a lot of them. First up -let's give U2's Where the Streets Have No Name a whirl and see what we come up with.

First, start with a nice healthy dataset of all streets in the contiguous USA and use some Geographical Information Systems savvy to process it. I'm fortunate to have access to the 2012 version of the Tom Tom data for North America which contains over 15 million street segments.

Second, apply a few of query analyses to extract any street segment without a name, discounting outliers like connectors, ramps, slip roads and such like. The result: a LyricMap of 3.5 million streets with no name, the beauty of which is that I don't need to worry about labelling because, well...there aren't any!

Finally, map each road segment with a huge dose of transparency so at the final scale the map shows areas that contain relatively few streets with no name as dark as the background. Where there are numerous streets with no name, the overlapping transparent symbols create a much lighter effect.

The map deserved to be styled as an homage to U2's classic 1987 The Joshua Tree which contains the track.

The overall pattern suggests that it's streets in rural areas that have no name. Pretty much all the major cities appear dark indicating a low number of streets with no name. This makes sense...the dataset contains every road in the U.S. and many of them would be dirt tracks. Despite there being over 3 million separate segments on this map there isn't much sense looking at the detail for a particular city...there are so few it makes the map sparse as the following larger scale map of California illustrates.

That said, if you want a giant 36 inch version at 300dpi then you can download one here. It's 12Mb.

Of course, there's more work that could be done to eliminate more categories of roads but hey - this is just a bit of fun. I've got plenty more geographically inspired LyricMaps planned so stay tuned!

Acknowledgments: Tom Tom data used and published under licence using Esri technology.

Wednesday 21 May 2014

I would map 500 miles

When The Proclaimers released Sunshine on Leith in 1988 I was just about heading off to University (to study cartography and geography - that bit is important). They were not to my musical taste...why would I want to be beaten up for liking such a dreadful duo? Little did I know that over 25 years later I'd be making a map relating to one of their first and most celebrated ditties I'm gonna be (500 miles). If you want the background read on...if you want to see my map, scroll to the bottom.

The song is renowned for the lyric But I would walk 500 miles. And I would walk 500 more...blah de blah blah.... And so fast forward to 2014 and the following popped up in my twitter stream.

Now it's clearly tongue in cheek and fair play to Hazel McKendrick...I haven't seen anyone tackle this cultural dilemma before and she had a good go. Where, indeed, were The Proclaimers going to walk 500 miles to from Leith? And what about the 500 more? Unfortunately she used two perfect circles at the nominated distance around Leith but too late, another viral map is born and all the usual suspects begin clamoring to heap praise upon it.

I and a number of map-minded people folded our arms and began finding fault because the circles shouldn't be so, well...circular! Yet again someone had done something wrong on the internet (thanks to Barry Rowlingson for reminding me of the well observed XKCD cartoon).

Great idea. Nice bit of fun but...wait...the Web Mercator projection distorts shapes and areas pretty markedly. If you draw a line indicating 500 miles around Leith on that projection it would not be a circle.

Here's the classic example from The Economist on the threat from North Korean missiles that made the same mistake...

And here's the correction they were forced to publish after they had redrawn the lines properly and with respect to the projection used for the map...

Now it's questionable whether marking the range of North Korean missiles incorrectly is more or less dangerous than the lyrics from The Proclaimers (I guess it's a question of taste) but either way McKendrick's map is wrong. And then what about the fact that reaching Iceland would require them to walk on water? Now we're stretching the bounds of their talent just a little far with that one surely!

So, as a self-respecting cartonerd I re-did the map...

I still used Web Mercator and placed 500 mile and 1000 mile geodesic buffers around Leith (using the same huge assumption as McKendrick) to show the real distances as they appear on this map. These represent the theoretical extent of how far they might walk so if they went off-road and walked in a straight line that's where they would end up (notwithstanding the small matter of the wet stuff).

I also went a little further and used a bit on analytic acumen to calculate how far 500 miles would take them using the European road network. Then I calculated how far they could get by going 500 more. Those areas I show as shaded so we can see how far they would walk on land. I took some liberties...I presumed they only walked on roads and of course, they may know of sneaky short-cuts or go roaming cross-country. I also presumed the ferry journey's equated to a walking distance when they most likely sat down and had a rest (though if they walked round the deck then the eventual distances need reducing slightly)

It's not perfect (there's no North Sea ferries to Scandinavia and the Brittany ferry is also missing) but it's better than shoving circles on a Web Mercator projection and calling it cartography. The correct version applies knowledge of how maps work to make a sensible, correct map...even though the theme is distinctly daft and I still hate the song with a passion. I hate poor cartography more though.

That said, McKendrick's map has nearly 2,000 retweets at the time of writing. Mine? 88. Proof positive that actually nobody gives a shit about quality anymore...or when someone has gone to the effort of providing a correction they do their very best to ignore.

Update: Thank you to all the people who have read this since posted. And a particular thank you to all the other nerds out there who have found fault with my version. I have updated the map to make the necessary corrections and disclaimers.

Update 2: I couldn't resist...I did a Where the Streets Have No Name follow-up map...and I'm now thinking of all the other geo-related maps that can be made. I'm calling them Lyric Maps.

Update 3: Funny how frivolous work gets noticed...I've written an update in a new blog post called Pedantic cartography.

Monday 19 May 2014

Spreading Light, Wasting Light

This blog entry is about mapping, honestly...but to get to my point I'll start with Dave Grohl and then get to Robert Downey Jr and Steven Feldman...bear with me.

On a recent flight I watched (for the second time) the great documentary on Sound City studios by Dave Grohl. The iconic music recording studio in Los Angeles was one of only a very few in the world to house a custom Neve 8028 24-track recording console designed by Rupert Neve. It was a hand-wired analog device which acted as the interface between the musician and the tape used to record the music but it was the console that gave the end product such a rich, unique sound. Often, musicians would need to play their track over 150 times to get it as they wanted it with all the imperfections ending up on the tape. They not only had to master their trade but be dedicated to giving their best live performance that would become the recorded piece. With only 24 tracks available on the console, the producers also had to be prudent and understand how a complete track was to be constructed to achieve their intended final sound.

The story is ultimately one of decline of Sound City as a viable business (it closed in 2011) despite it being the birthplace of countless classic albums produced in the late twentieth century as digital recording appeared and along with drum machines and other digital instruments, allowed people to record direct to a computer. The benefit's of digital recording are clear - the entry level for people making and recording music are massively decreased; the costs are much lower to make a recording; and anyone with a computer can record music. By using a program like Pro Tools you can play a track once then work on your computer to change duff notes, alter the pitch, add a range of effects (curiously with an image of an effects pedal you'll never likely have even seen in real life) and record as many tracks as you care. In short, it's making music for dummies and we've seen a proliferation of music appear as a result, all of it seeking perfection through a processed approach. You actually don't even need to be a musician to make an album these days. No craft, no art, no expertise as such...just working with digital data that equates to music when processed in a particular way.

However, as one contributor put it eloquently, there's nothing of the musician in much modern digitally produced music. A huge amount is over-produced with multiple layers of noise. What made music recorded through the Neve board at Sound City so immersive was the imperfections; the fact that you're listening to a real person play a real instrument with all minor imperfections in their playing exposed. It gave the music a 'feel' and a human quality that is difficult to express but which can be easily heard. It's an audible aesthetic and one that cannot be replicated in the same way using modern technology. The same commentator went on to say that yes, music recording has opened up like never before but he challenged us to consider whether it meant there was any better music out there. His thesis was simple..that all that has happened is more people with a lower level of ability or understanding of music (playing, recording, producing) now make music - but that there's a much higher proportion of poor music as a result. It's harder to find the quality any more because quantity sells.

Back to cartography - but as anyone who has read my blog before will realise, the above tale is pretty much verbatim my views on a lot of modern mapping. The death of expertise and massively reduced barriers to making maps has given us quantity but has seriously diluted the quality. People are becoming blinded to high quality mapping because they're consistently told to go look at this or that 'great' map by people who probably couldn't tell the difference anyway.

So my latest gripe is with the plethora of animated maps of social media data that are using CartoDB's torque engine. I like what CartoDB are doing and their torque engine is a very simple way to animate time-dependent data. But what of the result - how is it being used? Take a look at the following map of how Robert Downey Jr's twitter account gained followers in the first 24hrs after his first tweet:

And the man himself even commented on the map:
So what does the map show? I think Downey Jr was spot just shows him spreading light. Actually, it doesn't really show anything at all, except for twitter's absence in China. So a huge global movie star gains followers in places where people live. Are we amazed? And I'll not even bother to go into the pitfalls of the problems of mapping and inferring anything from Twitter data (because I've done that before).

Here's another of the tweets that were posted around the recent F.A. Cup Final between Arsenal and Hull City:'s just flashing light. What purpose does it actually serve? Visually, I like the effect but it really only shows us that people tweet. And therefore tweets reflect where people are on the planet. And Arsenal are much more popular than Hull City. And perhaps my good friend Steven Feldman is the one responsible for lighting up the UK as a twitter loving Arsenal fan?

There's just nothing particularly substantive about making maps like this. Once you've seen one you've seen them all. The digital tools make making the map very simple but it doesn't mean we're seeing good maps. It's quite literally a data dump on a map. There's no sorting, sifting, no trying to extract an interesting story or communicate a highlight (no pun intended though this would be a useful thing to do!). Light is cumulative and brighter = more but why are we so fascinated by 'more' of everything?

When I look at the map I see flashing light but after a short while I lose sight of the light area (most tweeting in relative terms..and really, the only metric this map is capable of displaying) because the almost strobe effect of the single tweets in the sparse areas becomes more prominent. Is this really the right message? And when the map is saturated with tweets what are we seeing? Anything?

I find the story of Sound City and its demise in the face of the onslaught from digital music has many parallels with my area of expertise. Whilst there's no doubt making maps these days is massively improved on many of the older techniques it doesn't necessarily equate to there being better maps. Like Grohl, who is a master of his craft (whether you like his music or not), many musical experts can still find ways to make their music and embrace digital technologies as part of their workflow. Trent Reznor is also a perfect example of this. A musician who knows his craft but is hugely experimental and who can weave modern technology into his work expertly.

I'm not decrying technological innovation and progress - just lamenting the decline of the thought that people used to have to put into making a map. If it was worth making it'd take time...and so that cost alone was a good way to decide if making the map was worth the investment. These sorts of maps can be made in minutes but without any sort of cartographic craft you end up making maps of flashing lights that tell us nothing or, as the title of Grohl's last Foo Fighters record're simply "Wasting Light'.

Update 1: there was an interesting side debate on this topic where some were suggesting that frivolous maps are nice once in a while. I agree. Firstly that this sort of animated map of social media data is content frivolous but also cartographically frivolous. It's experimental and at the moment we're in a period of cartographic change where for the first time in a long time technology is outpacing best practice. Experimentation is good and we need to figure out ways to harness these new approaches and to develop new best practices. This is a challenge and one that cartographers need to embrace. Unless they do, all we'll see is more of this type of mapping and more people telling more people how great it is.

Saturday 10 May 2014

The worm is turning

This entire blog is a conduit to encourage better mapping by exploring and providing critique on the dreadful, the mundane, the inaccurate and the sheer bloody hideous maps that we sometimes see. It's about standing up for what's right in my area of professional expertise and trying to reassert the value of high quality cartography (even if it hacks a few people off...which it seems to regularly).

For a few years, the over 100 blog posts I've written have sought to explain why bad maps are bad and how they might be far more effective...but over that same period there's also been a dramatic increase in the proportion of poor maps and, more than that, a massive increase in the various media sites that regurgitate, promote and peddle cartocrap and which also contribute through their own less than optimal efforts.

But maybe the tide is turning? This week has seen two media sites post articles on the problems with online maps....that's right...the PROBLEMS with online maps. Music to my ears.

First, Ben Blatt at Slate wrote an article entitled "Bad latitude: The trouble with viral maps". Then Business Insider's Mike Nudelman and Christina Sturbenz got in on the act with "The internet is obsessed with maps - here's why it's gone too far". And what prompted all of this? Ironically, it may well be the NBC Nightly News map that caused me such ire I wrote my "Changing face of America" blog post which was then itself used as a basis for the article by John Brownlee in his FastCoDesign blog "The worst infographic of 2014 (so far)".

The Changing face of America cartofail was perhaps so awful it may well have jolted people to question what they see a little more; to not be so accepting of every map they see and promote to such huge levels of viral contagion. Maybe, just maybe, some have actually pondered why people like me get so worked up at what all too often appears to be the dumbing down of the art and science of making maps? Or maybe online media has just measured the pulse of horror over this particular graphic and this week we're seeing some sort of reaction.

There's probably something else going on...we're possibly just reaching a tipping point. Our social media feeds are absolutely saturated with maps. Really saturated. Just yesterday I saw these two awful efforts:

The first was actually from a 2011 article in The Atlantic by Richard Florida entitled "Mapping the anti-creative class" that I hadn't seen before (but in social media if something goes around once it inevitably goes round again and again). It's just an abomination. There's no cartographic control been applied at all. It's a load of map-like components dumped on a page. There's no thought to symbolisation, layout or meaning. But it wasn't the map that horrified me so much as the write up which began "Those terrific cartographers over at...". No...NO. This is not cartography. It's been made by someone who clearly shows no cartographic acumen. The reporter clearly has no background in assessing or justifying that comment. It's tantamount to libel to accuse the author of cartography.

The second is from an article entitled "This is what America would look like without gerrymandering" in Vox by Andrew Prokop. It offers a really odd (and methodologically questionable) way of redistricting the United States that is based on using an algorithm that splits a state in half using the shortest possible line...which they kept repeating until they had roughly the same number of districts as the 'real' map. They are pretty shapes but also pretty meaningless. By repeating the flawed approach they simply propagate the errors at finer resolutions.

All of these media sites have been guilty of promoting this sort of stuff. They scrape and aggregate then push it to the unassuming and the uninitiated. In a tiny corner of the world people like me voice our concerns but it's a hard fight against large, loud, noisy voices, likes, pluses and retweets. But what happens when the media get bored of writing the same articles? They tend to take the opposing view. It's a cyclic approach to's how so much of news media works. They build something up then knock it down again because then they have something new to write. The 15 minutes of fame that people have yearned for by creating maps they simply want to go viral may just be about to end because the backlash is beginning.

There's something ironic about Slate and Business Insider beginning to take a different stand since they have been two of those media outlets more than happy to promote cartocrap in the recent past. I'm not going to quibble though - if they bring this message to more people who then take a more critical eye to their consumption of online maps then that is a good thing. They will hopefully start to become a little more discerning, more demanding. Up to this point, the media have stoked the production of awful maps because they've been behind their promotion. If they begin to take a different approach then maybe people will also begin to think produce work of a higher quality with at least basic construction being applied sensibly.

Maybe I'm being a little altruistic. I don't for one minute expect a dramatic shift from quantity to quality. As someone who has, in a very small way, campaigned for better mapping across all facets of my professional and private work in cartography it's a shift I hope has begun. It's a huge ship to turn and there's always people who believe their own facts but maybe if the outlets they rely on to push their work change tack, they may have to revisit their own approach.

Thursday 8 May 2014

Hubble bubble, transparency and trouble

I recently wrote a blog highlighting the problems of using transparency on choropleth maps when they overlay basemaps. Mike Bostock's recently posted "Let's make a bubble map" provided a really great tutorial on thematic mapping but also highlighted the issue of transparency once again. Here's his final map:

Look nice? Well yes, at first glance it does. It's clean, modern and pleasing to look at...and remember, these days most people are only glancing at maps so that first visual impression is oh so important. It's not just about looks, it's about the message we see with our eyes and how our brains are interpreting it. The use of transparency on this map creates a confused message because at first glance do you see size as important or darker colours as important? Or both?

There's a trend in online mapping in particular that uses transparency as part of the symbology design at every available opportunity. Modifying the alpha channel can be extremely useful and gives us a huge amount of flexibility to design symbols that work, particularly given the interplay of often complex symbology that competes for space.  It also allows us to produce some really pleasing effects. The problem here, though, is that applying transparency at an individual symbol level means that where symbols overlap you get darker colours. That's not a desirable effect when we're trying to communicate something about a quantity represented by a variably sized symbol...because it communicates something extra that is meaningless.

A proportional symbol is really just a geometric shape that reflects the value of a point or of an area (represented by a point). The overlaps have no spatial meaning whatsoever. Cognitively, we begin to confuse out estimation of magnitude (by seeing size differences) with another estimation of magnitude (lightness or saturation of colour). The use of transparency here creates a pseudo-choropleth effect that demarcates areas of circles as different to one another in some quantifiable sense. It's like seeing a load of stacked Venn diagrams where the overlaps have some additive property we should be mindful of. Except overlaps on proportional symbols are merely a function of proximity of the locations as well as choices made about relative symbol size. Overlaps do not mark out special areas where 'more' of something exists.

It's a confusing visual message. Additionally, where we see a large number of smaller symbols overlapping a larger one, the overlapped transparency masks the larger (more important) symbol. Look at the difference between the areas around Los Angeles County CA and then Cook County IL. How many of us miss the large symbol near Cook County because of the overlapping smaller ones? - yet it is similar in size to LA County, which just doesn't have as many counties nearby so doesn't get swamped. The overlaps are far more prominent on the east coast than the west simply due to the geography of there being more counties...but the increased density that we perceive through overlapping symbols causes an additive colour effect overplay the actual data magnitudes. By using transparency we're adding visual heirarchy to the symbols that show smaller darker ones as more prominent. That's at odds with a map like this where larger sizes should be at least on the same visual level.

Bostock correctly reorganises his symbols so smaller sit on top of larger. Then, instead of using transparency there are two more useful ways in which overlaps are dealt with to avoid the problems caused by transparency. First, the use of a border the colour of the background of the map is sufficient to demarcate symbols by effectively using cut-out effects. The symbols remain on the same visual level so we simply see the relationship between size and value. Like this:

Alternatively, hollow symbols with a strong outline might be used. Again, this makes the symbols all sit on the same visual level so we see size of the symbol as the visual variable relaying the information. For this example, the sheer number of symbols may not make this as good an approach but it can be used to good effect in different circumstances depending on the relationship of the geography, data and symbol scaling employed:

Bostock does a lot of other good work in the tutorial, not least pointing out the benefit of a decluttered basemap, or that we may consider using population weighted centroids as well as the need for strong visual anchors in the legend. All solid advice. The final version of his map as a web map adds a hover tooltip and also highlights the county by changing the border to black - a very sensible approach to give clarity to what is selected and to use interactivity in a useful way.

While I'm writing this though...there's one other niggle I have...the name: bubble map.

The long-standing term used to describe this type of map is a proportional symbol map. Now before someone calls me out on this and points to the fact Bostock notes this clearly at the start and end of the blog well yes, he does (he also refers to it as a graduated symbol map which isn't quite the same). So why persist in pushing a new term when a perfectly good one already exists?

Charles de Fourcroy is arguably the first to use proportional symbols in a graphic to show demographic data (he used 1782). We had to wait until 1837 to see proportional width symbols used for flow maps (Henry Harness). It was probably Charles Minard who then used the technique of making a symbol proportional to a value as part of his differently sized pie charts to show the origin of meats consumed in 1851. And map-makers have been making (and calling them) proportional symbol maps ever since.
I appreciate Bostock probably wasn't the first to coin the phrase so it's unfair to pick on this example but it's symptomatic of a growing epidemic. Bubble charts are not new. They're proportional symbol maps. How much more perfectly decent cartographic history and relevant terminology is going to be reinvented? The connotation with the word bubble is that the symbols are circles. It's true that most proportional symbol maps use circles because they are often the most suitable (as in 'the perfect shape'). But here's a version with squares:

OK, I'd agree it's not as pleasing for this dataset but it can have its uses. If and when you use squares, hexagons or any other proportionally scaled symbol to map thematic data do we have do call them bubble maps too...or maybe each map sub-type now gets its own name...squarey map?

Anyway, I digress.

Transparency is your friend as a map-maker, but knowing when not to use it is as important as knowing when it can really help your work.

Monday 5 May 2014

Another day. Another hyperbolic map

Hyperbolic - of or relating to hyperbola, an adjective describing something that is overstated or exaggerated. And so to today's hyperbolic map.

The work is called Isoscope and is by students at Postdam University under the guidance of Till Nagel. The write-up is in The Atlantic by John Metcalfe entitled 'A striking new way to visualize mobility'. Well...'new' and 'striking'...what a fine way to start a Monday morning. I checked out the article hoping to be cartographically amazed. Only, once again I found myself exhaling a deep sigh. Metcalfe describes Isoscope as a 'beauteous, immersive experience'. He also litters his piece with other glowingly positive terms. It's also Infographic of the day over at FastCo Design. Good grief. Is this hype just the reporting?...

I went to the project web site itself to be told Isoscope is an approach to capture the rhythm and pulse of the city; to find the boundaries of reachability, organically. It reveals traffic infrastructure, connectivity and natural boundaries. It's all about mobility and urban morphology apparently. but wait...mobility is way more than how far you can drive in a given time. It's more than's public transport, it's bicycles, it's the provision of safe bicycle lanes, it's pavements for walking on, it's a reduction in barriers (physical or socio-economic), it's about levels of fitness, disability etc...

Now let's be clear here...this is a student project. It's fine. It's teaching people how to use APIs and to make online maps. It's a fairly neat effort but...leave it at that. But no...not only does the project web-site over-inflate the work but then it gets regurgitated by a news media site hunting for any copy it can find to 'amaze' its readers for the few seconds they pass by.

Why we have to read about it being the next most amazing thing we've ever seen baffles me. It's not new to people like me. In fact, it's not new to anyone because this sort of work has existed for decades. Now if you are unfamiliar with it, that's a different matter but just because you weren't aware of this type of map does not, in absolute terms make it new. If it's the first time you've seen this sort of map do you not wonder if anything like it has been done before? How do you know what you're seeing isn't a rip-off, or poorly executed? Do you not approach such work with a hint of skepticism or at least a semi-critical mind? If not then you're lost my friend, you will read every new piece of hyperbolic cartography placed before you and neither care of its quality or efficacy. Like anyone, I love to be amazed and to see new and interesting work in my field of expertise. It's what pushes us forward and keeps things interesting. But too much of what gets passed around at the moment is neither new or amazing.

In terms of this map, you probably won't care that it's just an isochrone map...a 'service area' that can be calculated from a given point to all other points that fall within a search distance based on some criteria - in this case drive times as specified in a database. The term isochrone was coined by Francis Galton in 1873 "[I] propose to employ the word isochrone (equality of time) in a special sense..." (hat-tip to Joshua Stevens for reminding me of this). In fact, the use of isolines (lines of equal value) in map-making can be traced back to the 18th century. The Halley isogonic map (below, of magnetic declination) is possibly the first use of contoured curves of equal value. It was published in 1701.

That's over 200 years of prior art...and we've been making isoline maps and isochronic maps ever since. Don't believe me? Check out Google Images using the search term 'isochrone map'.

So back to the Isoscope application. It's simply a way to show isochrones for certain temporal distances around a point the user adds to the map. It calculates drive times based on a model of traffic condition at different times of the day in relation to the maximum speed limit of the road segments. So it's really a time-slice isochrone map capable of showing us different views at different times. You can also add a 'pedestrian' isochrone to show how far you can walk in a given time. Except it's not very accurate.

Here's a 10 minute drive time isochrone around where I used to live in London at peak morning rush hour.

It's wrong. It's hideously wrong. I added the red squares highlighting a few key junctions where you may be backed up for 20 minutes or longer. These critical junctions in the network would dramatically reshape the isochrones. I know because I needed to get to the University from my house - so much so that I switched to a bicycle and also walked. It took 12 minutes on a bike and about 25 minutes to walk. So let's zoom in and check out the 10 minute pedestrian isochrone.

I added the red dashed line - it's a distance of about 1200 feet (360m). That segment of the journey used to take me about 4 minutes. And what happened in the area I marked with a red square? There is no barrier, no impediment to walking to there in about 1 minute from my house. It's just an irrelevant blue blob that does not in any way represent where you can reach within a 10 min walk from my house. However nice you think the map just lied.

So the map is, as with a lot of maps, only as good as the data you pour in. Maps made by people in one city, yet creating a map for the whole world because the data exists...except the data is really not very good at doing the one job it's supposed to be doing and no-one bothers to do any ground-truthing or checking. Why? Because we're more interested in creating a beauteous, immersive, new and striking map than being overly concerned about the content (that and it's not really feasible when you're trying to map the world). But wouldn't you check areas you know well? Does the data actually do what it says or not? perhaps some estimation of error might be stated so we can proceed in our own interpretation with caution?

In terms of design, the use of a dark basemap and bright, single colour polygon overlays, with a nice dose of transparency isn't particularly striking either. We've seen a lot of maps styled that way recently.  Don't get me wrong...I like the look (and have made maps with a similar aesthetic myself)...but it's not new or striking. As for the typography? It's a little clumsy.

So, I wonder about all the things I am unfamiliar with that may also be new, or not as the case may be. Open your eyes people...go beyond the rhetoric, the marketing, the tediously simple journalism and learn a little of what you're consuming. A very good student project yes, but not a new or striking map.

I wonder what hyperbolic map will drop across my desk tomorrow?