Monthly Archive for April, 2009

ARRA funding map

ARRA Funding Map

Lots of maps are coming out that document when, where, and how stimulus money is being spent through the ARRA, like these at the Foundation Center. With all of the reporting, accountability, and transparency required of ARRA grant recipients, I’m sure we’ll only be seeing a lot more of these in the future. Recovery.gov directs traffic to states’ Web sites where some of this data is appearing. I’m looking forward to seeing more and more mash-ups and interactive maps and graphics as developers and designers get their hands on this stuff and data from other sources that track stimulus money, like Onvia.

Our Map

For now, we decided to get involved by putting together a static map that shows where our ARRA tax dollars are going for energy-related programs administered by the DOE. As underlying layers, the map shows states’ historical energy consumption trends and their projected trends required to meet consumption goals set for 2012.

I’m sure we could all talk about the politics around ARRA funding and energy consumption and how this might or might not be shaped by patterns that the map does or doesn’t show. But to me, a few of the most interesting things about this map are related to its design:

1) Encoding data in state boundaries

I’ve always been attracted to National Geographic political reference maps, with their countries each outlined in a different color. On those maps, outline color clearly helps distinguish one place from another. Plenty of other maps use enumeration unit outlines to represent data, too, like those that categorize administrative boundaries using line weight, dashes and dots, etc. I wondered what was to stop the application of this idea to a thematic map? Why not try to take it one step further and encode numerical data, as opposed to nominal data, in unit outlines? I haven’t seem many examples of this.

The main limitations here are line weight and unit size. Line weight has to be heavy enough so that color can be seen and read. For my map, this seemed to work best above around 4 pts. Only thing is, as enumeration units get smaller, the outline can eat up more interior space and obscure the presence of a second data set, which in this case is the historical energy consumption trend, encoded using unit fill color. So, I had to cheat a little bit with some small states and states with small pieces (e.g., Delaware and Maryland) and decrease the line weights a bit under 4 pts. I don’t see this approach working very well with really small enumeration units like US counties, unless the map scale is really huge.

2) Color selection

The challenge here was to select colors for three data sets (historical energy, projected energy, and ARRA money) that not only encoded data properly but were harmonious (i.e., not competing or ugly). The historical energy data set has a natural midpoint around zero, so it needed a diverging color scheme. On the other hand, the projected energy data, having no midpoint, required a sequential scheme (thanks to ColorBrewer 2.0 for both sets of specs). Proportional rings for ARRA money just needed to be readable and look nice on top of the other colors.

Here are some earlier attempts at getting color right. In my first try, I used a grayscale sequential ramp for the historical data (state fill color), matching the middle value to the map’s background for a pseudo-diverging ramp feel. But this seemed overly subtle and downplayed the importance of clearly distinguishing states with decreasing and increasing energy consumption trends.

First attempt at color.

First attempt at color.

So, my next try was to replace the grayscale ramp with a true diverging ramp. Yuck. The mix of red outlines and fill colors bothered me on an purely aesthetic level. Other diverging ramps with other hues in them produced similarly ugly results.

Second attempt at color

Second attempt at color.

The final colors for historical energy consumption trends (blue-white-red) seem to best emphasize the data’s midpoint, with red doing its part to connote “alarm” in the states with a poor track record. The projected energy consumption data set is now lower down in the visual hierarchy (shown using a grayscale color ramp on state outlines), but this seems to be acceptable compromise. Using gray prevents these two ramps from competing for attention or overlapping and confusing the map reader. From my perspective, at least, it also results in an (yes, subjective) improvement in overall color harmony.

Other thoughts about the ARRA funding map? Please add them to the comments.

Virtual Globes are a seriously bad idea for thematic mapping

Google Earth is amazing. As we’ve commented here before, it continues to blow our minds and has also done wonders for the popularity of maps. And let’s be honest, it looks super cool. There is no doubt that Google Earth is much sexier than that boring old atlas collecting dust on your shelf: It’s interactive, seamlessly integrates distributed data sources, animates the surface of the earth over time, facilities virtual communities, can be customized by both developer and user, etc, etc. It’s hard to not be impressed.

So all of our maps should be in Google Earth, right?

Wrong.

In fact, despite recent efforts to create a suite of thematic mapping approaches, Google Earth is a terrible environment for presenting many kinds of thematic maps. I’d go so far as to say that the 3D prism maps and 3D graduated symbol maps we see popping up in Google Earth are pure chart junk, of the kind Tufte warned us about repeated for past 25 years.

3D prism map of population in Google Earth

3D prism map in Google Earth (blog.thematicmapping.org)

3D human figures as proportional symbols

3D human figures as proportional symbols (blog.thematicmapping.org)

CHART JUNK

Chart junk takes what should have been a simple-to-read graphic and makes extracting information (1) slower, (2) more difficult, and (3) more prone to reading errors, because of excessive ornamentation and unnecessary design additions—like adding a 3D effect that communicates nothing in and of itself but simply “looks cool.” This is not idle speculation: Research consistently shows chart junk and “redundant ink” hurt otherwise fine graphics.

Want to see for yourself? Download these two example KML/KMZ files from blog.thematicmapping.org and run them in Google Earth. While you’re looking at them try to extract numbers or compare places: KMZ File 1 |  KML File 2

“BUT THEY LOOK COOL”: A TECHNOLOGY IN SEARCH OF A PROBLEM

As Abraham Maslow said, “If the only tool you have is a hammer, you will see every problem as a nail.” This seems to be the case with virtual globes and the developers who love them and insist that any and all kinds of thematic data belong there. Instead, I’d challenge us to take a step back and ask,

WHY DO WE MAKE THEMATIC MAPS?

For a long time folks like Robinson, Dent, and MacEachren have been arguing that thematic maps exist to support two basic tasks: (1) the ability to extract numbers/facts about specific places (e.g., 15C in Paris) and (2) the ability to judge those values in geographic relation to other places (e.g., 5C warmer than London, about the same as Milan). In other words, we want both specific details and overall patterns to be obvious on our thematic maps. And we want all of that AT A GLANCE.

The problem with digital globes (as with all globes) is you can’t see half the planet and, due to curvature, really only about a 1/3 of the planet clearly at once. Which leaves us with a conundrum: If you’re only mapping a small place (e.g., a country), why do you need to have it on a globe? And if you have a global dataset, why would you allow your readers to only ever see ½ the data at once? They can rotate the globe (more on this later) but they’ll never be able to see the entire dataset at once. That makes understanding overall patterns very difficult, and asking folks to “remember” half of a global dataset while they spin the globe to the other side is far, far beyond the meager limits of our working memory. If you’re not convinced, just try it.

KNOW YOUR HISTORY

What makes these recent developments even more frustrating is that in the 70s and 80s, with the advent of digital map making, cartographers flirted with, and largely rejected, faux 3D prism maps and 3D graduated symbol maps (like the two examples above) since they suffered from several limits:

    1. visual occlusion (not all of the map can be seen at once since some places hide others)
    2. people suck at estimating volumes, especially of complex shapes (e.g., try estimating the size of moving van you’ll need for your home)
    3. mental rotation of complex shapes is extremely hard, so hard that it is often used as a measure of intelligence in IQ tests.

Many a thesis and dissertation was written in the past 40 years demonstrating these limits to human visual processing.

The nice thing about Virtual Earths is that you can rotate them, so the problem of visual occlusion is solved, right? Yes and no. Yes, interactivity and the ability to rotate the globe can help reveal hidden places, but no, these virtual globes introduce a significant extraneous cognitive load because the user must now think about controlling the globe (not always easy with a mouse) while also trying to focus on the thematic content. In fact, adding a complex task, like visually acquiring the Google Earth controls and then trying to figure out how to move/scale/reposition the globe between two other tasks effectively “flushes” short-term working memory. It’s a kind of mental sorbet, which is why giving folks something distracting to do is a common trick in memory tests (they lose their train of thought). Why would we deliberately do this to our map-readers?

BIG PROBLEM: INCONSISTENT SCALE

In the examples above it is really hard to judge relative sizes. Why? Because the scale of the symbols is constantly changing, and the ones closer to the viewer are much larger (and at a different scale) than the ones far away. Given that it has been long established in cartography that people are terrible at estimating sizes, and even worse at estimating volumes, it is utterly inane to compound this failure by drawing the symbols at different scales. Of course it is worse than this: Rotating the globe slides each symbol through its own scale transformation path, changing in size with every pixel the maps are moved.

This is an absolute rule: If you want to give people the best chance to judge the relative sizes of objects, they should all be drawn at the same scale.

STILL NOT CONVINCED? LET’S DO SOME USER TESTING

Judging height is critical to the success of this map, yet most heights are obscured

Judging height is critical to the success of this map, yet most heights are obscured

TASK #1: As quickly as you can, how does Nepal compare to Uzbekistan?
TASK #2:
As quickly as you can, find all of the other places on the map similar to Nepal? Which place is most similar? Which one least?

Hard, isn’t it? To be honest, it shouldn’t be: A regular 2D classed choropleth map or proportional symbol map would make short work of those questions. So what did we gain by extruding the countries up into space? Not much that I can see.

    1. The Lack of a zero-line referent makes it hard to judge absolute magnitudes.
    2. The “fish eye lens” effect mean each prism is viewed from a different angle than its neighbors, making comparison just a little bit harder as we have to mental account for these differences in our estimates.
    3. It is hard to judge the height of something when you are staring directly down at it. This matters because height is the visual variable that does the “work” in this graphic—it’s how the data are encoded visually. Why obscure the very thing map-readers need to make sense of the graphic (e.g., the side-view height of each polygon)?

SOLUTIONS?

I need to be convinced of two things: (1)  something is fundamentally wrong with our proven and highly efficient planimetric thematic maps, and (2) that reprojecting this data onto a virtual globe somehow solves those problems. Otherwise, we truly have a cool new technology in search of an application, and that’s just putting the cart before the horse.

Some suggestions: First, unless the 3rd dimension communicates something and isn’t merely redundant data already encoded in the colors, sizes, etc., do not include it (for all the reasons outlined above). Second, if you want folks to perform “analytical map reading tasks” such as estimating relative sizes, distances, or densities, keep scale constant. Third, do not obscure parts of the map behind other parts if that isn’t inherently relevant to the data (e.g., this is fine for terrain visualization). Fourth, and most importantly, do some user testing before presenting a new technique as the best thing ever: It’s how research works and why it is important.

So what things are Google Earth (and other Virtual Globes) good for? The consensus around here is (1) to engender, quite powerfully at times, a qualitative “sense of place” or “immersion”; (2) for virtual tourism (e.g., sit on top of Mt Everest) or virtual architecture/planning; and (3) to perform a kind of viewshed analysis and see what can and cannot be seen from locations (line-of-sight). All of those are inherently 3D-map reading tasks in which the immersive, 3D nature of the map is important. By comparison, population data (one number per country) is NOT inherently 3-dimensional and is only made to suffer when dressed-up in prism maps and 3D figurines.

Cartography, like all good design, is about communicating the maximum amount of information with the least amount of ink (or pixels). The world is just too complex and interesting to be wasting our ink/pixels on non-functioning ornamentation.

SXSW: Axis Maps Roadshow

A couple weeks ago I was lucky enough to get invited to the SXSW Interactive conference to speak on a panel called Neocartography: Design and Usability Evolved. Here are some collected thoughts I had from running through the panel again in my head.

Do you need a cartography degree to make maps? As the only trained cartographer on the panel, they just couldn’t wait to ask me this question (could I really say that Stamen’s “non-cartographers” shouldn’t be making maps?). I gave the popular answer, “No,” but with a caveat: “You just need to care about cartographic design.” Elegant design and clear communication are universal to all aspects of design. Cartographers have a slight leg up in the map game because we’ve been using our design chops to get good at applying these universal concepts to maps, but concepts like subtle use of color, visual heirarchy and map / UI composition can directly be applied from graphic design to map design. Incidentally, this is the hardest stuff to teach to cartography students. However, there is a lot of cartographic design that is uniquely geographic. Issues like projections, thematic symbolization and generalization don’t exist outside of maps and largely exist because of the challenges of representing a complex world on a small, flat piece of paper. These same issues remain even moving from paper to the computer screen, but unfortunately they are largely ignored. On a preachy note, I think it is our responsibility as cartographers to CONSTRUCTIVELY engage ourselves with the new mapping discourse.

What’s with neocartography? Neocartography is a tricky definition (one that I think is changing every day) so take the coward’s way out and define it as:

You know… the Where2.0 crowd.

But “Where2.0″ covers it pretty well. Location (that’s the where) is EVERYTHING. It’s an on-demand (that’s the 2.0) reference-map world where apps need to know WHAT you’re looking for so they can tell you WHERE it is. A lot of cartographers (especially those educated in Geography) probably feel disengaged with the new movement because they are looking for “Why3.0.” We want to make thematic maps that explain the world instead of just locating a tiny part of it. And unbelievably, with two people on the panel who helped build it, we never showed off Geocommons Maker and its thematic mapping to the audience. We could have started the Why3.0 movement then and there!

What about the 9,000 lb Google shaped elephant in the room? Instead of listening to me prattle on about projections and choropleth classification schemes, it seemed like the audience would rather hear what Google, represented by Elizabeth, their Maps UX Designer, had to say about mapping. Me too. Even though we are both making maps on the Internet, our issues couldn’t be more different. Where we can agonize over cartographic and UI issues, Google constantly needs to consider issues of scalability. With their maps viewed by millions of people (horrible problem to have, right?), design decisions take on massive significance. The UI and interactivity set worldwide expectations on what an interactive map should be (look at panning / zooming controls on all the major map providers to see their influence). They’ve become masters of the universal elements of cartographic design but have not addressed (or have been constrained by) the uniquely cartographic issues. Because Google sets the tone for mapping on the web, the web-mapping community has believed that these issues cannot or should not be dealt with.

Anything else? Just a couple things:

  • Cloudmade and OpenStreetMap are going to be huge. They are going to improve the state of cartography on the web and engage both experts and the public with mapping in entirely new ways. 
  • GPS is coming to social networks. This is going to be MASSIVELY HUGE. In 3 years, “location-aware” won’t be a buzzword anymore, it will be an assumed feature. There is going to be insane amounts of spatial data and I, for one, cannot wait to face all of the display challenges it’s going to pose.
  • Stamen kicks ass and they’ve set the bar high for top-shelf online mapping. It’s hard to share a stage with Mike Migurski when he has such awesome maps and visualizations at his disposal. What a show-off.
  • It was great to meet Elizabeth and some of the Google Maps team. I wish I could have pried more Google secrets from them but they’re too tight-lipped.
  • Andrew Turner at FortiusOne is one of the most plugged-in, active people working in the neocartography field. Thanks to him for putting together a great panel and keeping us in line.
  • Everyone at SXSW had an iPhone.
  • Everyone communicated via Twitter.
  • Favorite quote: “The difference between unemployed and self-employed is only in your head.”
  • Favorite panel: How to Give Better Presentations – To unfairly summarize, be gimmicky to get people’s attention, play to their emotions, and don’t split their attention between what they see and what they hear.
  • I honestly cannot recommend this conference enough. Getting to be around the leaders in the technology field was an unbelievably energizing experience. I met some wonderful and inspiring people and I could feel the world changing over those five days.