Last Thursday’s entry on the use of charts and graphics led me to realize there were a few more “basic” items I needed to include. Rather than rewrite or add to the Thursday entry, I decided to just add this supplementary entry. I hope you’ll indulge my laziness.

Using common measurements

One of the most important tenets of table or chart-making is making sure that you’ve got two or more items that can have comparable attributes that you can quantify or display visually. Using a completely hypothetical and somewhat ludicrous comparison, suppose you had a document that included jet aircraft and oak trees. About the only thing you could compare between those two items would be their size.

You wouldn’t be able to measure a jet’s growth rate, ability to photosynthesize, or branch/leaf structure; likewise, you wouldn’t be able to measure an oak’s thrust, maximum speed, or maximum takeoff weight. You could get creative and compare the aerodynamics of a tree’s leaf with an aircraft wing. Or, if your kids are out playing in the yard imagining that the tree they’re climbing is an aircraft, then you might get fanciful and compare the number of passengers an oak could handle compared to a 787. (I have seen instances of charging a mobile phone from a plant, so you might be able to do a power comparison between the two, but that’s stretching things a bit.) However, for the purposes of technical communication, those are probably not useful comparisons.

Using colors and graphics effectively

Different colors have different connotations and cultural meanings. Operating as I do in an American/Western environment, red usually connotes “stop” or “danger,” yellow equals “caution,” and green depicts “proceed” or “good to go.” Street signs throughout much of the world use similar conventions. However, if you were reverse these conventions in your graphics–say, using red to equate to a favorable condition and green as a color indicating danger or the need to cease operations, you can mislead your readers unintentionally (of course if you’re doing that intentionally, please read the next section on communicating ethically).

In my experience USA Today has been the home of the infographic. For decades they’ve been incorporating pictures, symbols, and numbers to share statistical information with the general public. Where possible, they try to make some aspect of the data part of the visual.

Graphic conventions

In the last post I discussed the left-to-right, up-and-down conventions of the Cartesian coordinate system. In brief, as you move from left to right on a graph, numerical values increase. Likewise, if you’re moving from a lower part of the graph to a higher part vertically, the numbers also increase.

However, did you know that these conventions also appear in non-numerical graphics? Many times in movies, say in a confrontation between two armies, the “good guys” move left to right across the screen while the “bad guys” move right to left. Good guys in peril fall down pits toward the bottom-left of the screen.

Likewise, aerospace business images often include an object ascending upward or to the right. Don’t believe me? Try these:

Mars Society (to be fair, this logo also includes the ancient zodiac symbol for the planet Mars)

You get the idea. Of course these are engineering firms, so they might be more likely to use a Cartesian model of thinking, but the overall impression remains: positive! A Western company with a logo pointing in the direction of up and to the right is trying to convey progress! Moving forward!

Even political campaigns are not immune:

Mind you, not every corporate graphic is oriented this way–a lot of corporate logos are mostly or partly symmetrical, which conveys a different message: a sense of order, harmony, solidity, or structure. A lot of thought goes into graphics, so it’s not just a matter of “making something pretty.” Whether you are stating it boldly or subtly, the images you use to depict your organization say something about who you are.

Communicating ethically

In addition to comparing mostly similar items, you also need to be comparing your measurements honestly. For example, as I mentioned in the Thursday entry, if an organizational budget’s rate of growth is being reduced (i.e., the budget will increase only $5 million instead of the hoped-for $10 million), that is not an actual cut. However, you will note that this does not stop legislators or advocates from calling it such.

In similar fashion, let’s say you’re working for a large industrial concern that has a process known to kill fish in a local river. If the company has changed something in the process that reduces the number of fish being killed, it’s a bit disingenuous to use your graphics to say that your company is “saving” that many fish.

Another danger in presenting statistical data is leaving out critical facts. For example, if you claim that your solar plant is good for all forms of life but plants or animals are harmed by the mirrors or the manufacturing process of the solar cells, that is not the same as harm-free.

Because we’ve become such an image-focused society, it can be very easy to mislead or distract your readers/viewers by connecting one image with another. Posting a picture of Stalin or Hitler next to some otherwise-factual information will cause your target audience to react in specific, visceral, and negative ways that will tend to affect whatever data is in close proximity. In similar fashion, placing a figure of a beloved national or international figure next to some horrific facts (pick your least favorite) to create a “halo effect” can alter a reader’s visual perceptions. It might be a common tactic of internet memes, but is (usually) not an ethical way to use graphics to communicate a message in a professional context.