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Light entertainment: this looks like a bar chart

Long-time reader Daniel L. said this made him laugh.


This prompted me revive a feature I used to run on here called "Light entertainment." Dataviz work that are so easy to ridicule that one wonders if they weren't just made for the laughs. See all previous installments here.

Daniel also said it fails the Trifecta Checkup. What is the question the chart is addressing and what's the message? It's a bar chart, the axis not starting at zero, with multiple colors and Moire effects. and missing labels!


Verging on trust

I’m not quite done with that Verge survey on social media popularity. Last time, I discussed one of the stacked bar charts about how much users like or dislike specific brands such as Facebook and Twitter. Today, I look at the very first chart in the article.


This chart supposedly says users trust Amazon the most among those technology brands, just about the same level as customers trust their bank.

The problems of this chart jump out if we place it side by side with the chart I discussed last time.


The chart on the right has six categories while the one on the left has only five categories. The missing category is “somewhat distrust.” It’s not likely that the "trust" question has asymmetric choices of “greatly distrust”, “somewhat distrust”, “neither trust nor distrust”, and “greatly trust” so I suspect the omission is unintended.

On the "trust" chart (left), the “no opinion/don’t use” category is painted yellow while on the right chart, it is colored gray. The yellow bars represent different things on each chart.

Also inconsistent is the order of the bars. Chart designers should be aware that readers develop certain expectations when going from one chart to the next.

The greatest mystery concerns the lengths of the yellow bars on the left side. I suspect that the brand labels have been wrongly applied. If we believe these labels, then almost 50% of users have “no opinion or don’t use” a bank. That seems highly unlikely. Further, the more popular services such as Amazon and Google apparently have almost double the proportion of users who have “no opinion or don’t use” versus Twitter.

I'd guess that the yellow actually stands for "greatly trust" and the "no opinion/Don't use" has been inadvertently dropped from the chart so part of the legend is incorrect.


Using a bardot chart for survey data

Aleks J. wasn't amused by the graphs included in Verge's report about user attitudes toward the major Web brands such as Google, Facebook, and Twitter.

Let's use this one as an example:


Survey respondents are asked to rate how much they like or dislike the products and services from each of six companies, on a five-point scale. There is a sixth category for "No opinion/Don't use."

In making this set of charts, the designer uses six different colors for the six categories. This means he/she thinks of these categories as discrete so that the difference between categories carries no meaning. In a bipolar, five-point scale, it is more common to pick two extreme colors and then use shades to indicate the degree of liking or disliking. The middle category can be shown in a neutral color to express the neutrality of opinion.

The color choice baffles me. The two most prominent colors, gray and dark blue, correspond to two minor categories (no opinion and neutral) while the most important category - "greatly like" - is painted the modest yellow, paling away.

Verge sees the popularity of Facebook as the key message, which explains its top position among the six brands. However, readers familar with the stacked bar chart form are likely looking to make sense of the order, and frustrated.


In revising this chart, I introduce a second level of grouping: the six categories fit into three color groups: red for dislike, gray for no opinion/neutral, and orange for like. The like and dislike groups are plotted at the left and right ends of the chart while the two less informative categories are lumped toward the middle.


I take great pleasure in dumping the legend box.


Now, when a five-point scale is used, many analysts like to analyze the Top 2, or Bottom 2 boxes. The choice of colors in the above chart facilitates this analysis. Adding some subtle dots makes it even better!


Because this chart is a superposition of a stacked bar chart and a dot plot, I am calling this a bardot chart.

Also notice that the brands are re-ordered by Top 2 box popularity.