649week05 → The Normative Perspective
Normative, or prescriptive, ways of looking at infoviz guide us toward a narrow set of fashionable design choices. You may guess from the words “narrow” and “fashionable” in the preceding sentence that I have mixed feelings about this perspective on information visualization. This is certainly a valuable perspective but, before we explore it, I’d like to insert two placeholders into your thinking. The first of these has to with the position of infoviz in relation to other disciplines. The second has to do with users, contexts, and communities.
Above is a Venn diagram based on Table 1.1 of Card (1999), colored by ColorBrewer. Looked at this way, InfoViz may be said to inherit from several disciplines. There’s no reason why InfoViz shouldn’t borrow the principles of these disciplines as far as they offer design guidance. Plenty of guidance is available in the worlds of data graphics, information design, and external cognition. Consider this Venn diagram, an example of external cognition that has been available for about 125 years, with many refinements along the way. The coloring comes from a contemporary cartographer, Cynthia Brewer, and a data graphics aid called ColorBrewer. ColorBrewer asks you to consider whether the variables you’d like to color are sequential (which is what I chose), diverging (two groups with subgroups), or qualitative (nominal or categorical). It shows examples of color schemes reflecting these choices on a map of the Southeastern USA, as well as a variety of encodings such as CMYK and RGB to implement these color schemes. The colors were selected by an experimental process where the researchers displayed maps using various color schemes to participants who answered questions about the maps.
The ColorBrewer work is similar to that of William S. Cleveland, documented in his 1985 book, The Elements of Graphing Data, Hobart Press, Summit, NJ. Cleveland displayed graphics and asked questions about the quantities shown to experimental participants. In addition to his own work, he also collected studies conducted by his colleagues at Bell Labs. His books are responsible, for instance, for a worldwide aversion to pie charts. Why? Because he found that it was more difficult for people to estimate the quantities represented on pie charts than on other graphical artifacts.
This raises the second of the two issues I’d like to consider, but before we’ve finished with the first issue. Let’s just make a note of the fact that we have privileged one issue: accurate estimation of quantities represented on a graphic. It seems fair to do so. If all else is equal, we certainly prefer the technique leading to accurate estimation. Let’s return to this subject after we finish with the first issue.
The first issue with the normative perspective is that plenty of guidance is already available for exemplary practice. Several disciplines offer useful principles. They’ve been doing so for a long time. There are a few writings on graphical principles throughout history and a steady stream in the last hundred years. So what do the prescribers offer?
If we think about design as constrained choice, it’s easy to see many graphical aids as making choices for us. I use the term “graphical aid” loosely when I mention Powerpoint, but this is surely the ubiquitous contemporary “graphical aid”. It, more than any other system, insists that we violate graphical practice as old as Aristotle. The prescribers of InfoViz practice, above all else, rail against chartjunk, such as that created by default Powerpoint settings.
This is not new. Christopher Alexander, in Notes on the Synthesis of Form, 1964, sets forth a compelling example of Slovakian shawls. Their golden age as prized souvenirs in the nineteenth century ended with the introduction of a new technology, aniline dyes. Slovakian shawls, formerly prized as delicate and subtle, then became burdened by a reputation as vulgar and uninteresting. Alexander’s insight into the interruption of this art form was to see that the key gift of the shawlmakers was to be able to recognize a bad shawl in a group of good shawls. Individual bad shawls would appear in the tradition, but they would not be repeated and gradually a high standard developed and could be maintained. The tidal wave of available colors from aniline dyes simply overwhelmed this facility. We can imagine a normative approach to rescue the shawl-makers from new technology just as Tufte has rescued us from Powerpoint.
The second issue has to do with users, contexts, and communities. A recent normative book shows an example of good graphical practice as (a) using high saturation for objects and low saturation for backgrounds. The picture in (b) shows just how bad things are when we reverse these. The problem with this good / bad dichotomy can be seen in a painting by Miro (c) and by a stock photo of peppers. In both cases, the goal is to make the eye restless. In the normative view, tranquility is prized and we can’t simply say that one approach leads to tranquility without identifying that as good. The problem of users extends not only to different contexts, but to different users and to the social construction of the meaning of information artifacts.
There are plenty of problems with a prescriptive perspective in any field, but it seems that the value of the normative perspective in information visualization has to do with popularizing and standardizing basic principles that have been, at least somewhat, improvements on previous standard practice. For instance, many academic works discuss how visualizations are badly designed by way of ignorance or abuse of basic principles of perception and cognition, but Tufte’s accessible writing serves as a gateway to popularize the notion that “chartjunk” is harmful to information visualization as a field, and many more people are able to understand these concepts and apply them to their own work. These prescriptions should not be taken as authoritative, and while they provide a good place to start, they should be recognized as simply that — a place to start — and should be read with a critical eye.
This is just a minor observation, but I thought Tufte’s 1983 critique of pie charts was pretty humorous (and probably accurate): “the only worse design than a pie chart is several of them”. Therefore, I was surprised to see a very similar graphic presented in Tufte 2006 (p. 131) without any sort of disclaimer (in fact, it was nestled amid the author’s endless praise of the artist, Minard). While Minard’s pie-chart map was just used as a color example and seemed innocent enough, in thinking about the normative/prescriptive perspective, it struck me that this could serve as an example of where this attitude can be unhelpful. If Tufte has established himself (and Minard) as an authority who’s presents all of the right ways to do visualization, than someone might read only Tufte 2006 and would understandably believe that the author endorses pie-chart maps. I guess what I’m saying is that when you set up that authoritarian dynamic (like in the prescriptive model), you stand a greater chance of being interpreted in an unquestioning, dogmatic (and perhaps incorrect) way, and this is counter-productive.
If I may say so, Tufte sounds like little more than a strongly-opinionated old man on a rant. I can appreciate much of what he has to say, but he says it in a way that makes it sound like if you don’t agree with him you are wrong.
Tufte’s prescriptions are quite extremist, with the plot at the bottom of page 124 of Tufte 1983 being much more difficult to read than the figure at the bottom of page 123, or even at the top of 124, yet he claims that it is objectively superior. He also seems to make fun of designers who do it “wrong”.
Following up what Jim said about not being consistent, in his introduction to the Small Multiple design he talks through a “splendid” drawing that clearly has an unnecessary line, which is in direct conflict to his ink-to-information obsession.
That said, I agree with him about PowerPoint.
There’s a semi-relevant article in Slate today about dogma in architecture (http://www.slate.com/id/2210507/?from=rss). One of the points the author makes is that architects naturally become dogmatic because, given the variety of solutions to any architectural design problem, how do you convince people that your design is a good one? Adhering to standards can validate your ideas. Of course, good design can also come from breaking the rules, so like those above have mentioned, the middle ground might be the best place to stand.
Re: Noah - “Tufte is a ranty old man”
He does certainly give off that vibe on occasion. (Many occasions..)
I think every graphic designer I’ve ever met (self included) kept a few Tufte books around for the pretty pictures - beautiful inspiration - but I think they all take him with a grain of salt too. Good concepts, but design “rules” were made to be broken… as long as you’re still effectively communicating. Not every graphic needs to by clean and simple to work, but if you’re worried about being effective, it’s a good place to start.
Tufte was fun to read as a “ranty old man”!
I don’t have a problem with normative ways of looking at Infovis, but it is a bit harder given the range of fields across which we as Information students routinely gather relevant information. Proscriptions seem to work fine within communities, but across communities, tone and intention can be more difficult to pick up.
In Tufte 1990 (p.67), he stated that information slices should be positioned within the eyespan, whichi I agreed partly. As we can see from the example he provided, 12 small pictures of trains’ signal lights (p.68), even though they were within my eyespan, it was pretty hard to tell the difference. So, I would say the first thing that affects how people make comparison at a glance is each pictures’ positioning plus their specialties other than “within the eyespan”, a very vague assertion.
To form a normative theory, my thinking is that it should be based on detailed figures or be proved right in many practical cases. In this case, it might define how long the eyespan usually is or the proportion between your eyespan and the distance you’re in front of that picture.
PowerPoint is an easy target for maligning, and it is hard not to fall in line with Tufte’s perspectives on some design principles. However, as with the example of the Calder I think it is important to recognize the possibility that Tufte’s perspective may be more broad and nuanced than it makes itself sound by the tenor of his writing. At least, I hope it is, because it is also true that if taken at tone value both he and Bertin come off in a manner most bickering.
Attempting to re-read the Tufte, I think his inclusion of positions that lack a stable founding in Real Politic evidence, like “Content Counts Most of All” (see Mick’s other post) and his admiration of Calder’s stag (I would assume fully aware of the transparent right antler) are clues to the importance of possessing a breadth to expression quite outside the tone of his writings.
Yes, his writtings are prescriptive and maybe even a little bit straight-jacketing. But, goodness knows I’ve dumped a few images into outlines and borders JUST to be decorative (and so did Art Deco and Arts Nouveaux, the best loved art movements of some populations of modern designers… for good or ill), and while Tufte’s writings might rail about the visual weight of extra forms creating vibrating, distracting negative space forms they have carried out their job of drawing attention to the drawings that were imprisoned in them and the messages in those drawings.
Sometimes, maybe quite sadly, people are more comfortable with agitation and instability than balance and stability. Especially given the reeling, rocking motion of social, political,and environmental destabilization in our day (and not only within the last quarter century, beyond that) it is perhaps more familiar than a sense of peace.
I begin to wonder if a Tufte, or at least the design principles of Tufte, don’t encompass more room for those kinds of errors and inefficiencies, if they are in the service of something. After all, I think it is mentioned, at the very least in Bertin, that design principles are GUIDELINES, and his presentation’s questioning, poisonous tone is perhaps there to remind us to question, perhaps Tufte, himself, as well.
That being said, it is definitely true he talks about important things. Anyone who invokes the old mark+mark = mark+mark+negative space is standing on fairly solid ground for design purposes, at least for as long as they stay there. It’s just that maybe the times or the audiences can demand, and even need some shaky ground, sometimes……