Checking the scale on a chart

Dot maps, and by extension, bubble maps are popular options for spatial data; but the scale of these maps can be deceiving. Here is an example of a poorly-scaled dot map: The U.S. was primarily an agrarian economy in 1997, if you believe your eyes. Here is a poorly-scaled bubble map: New Yorkers have all become Citibikers, if you believe what you see. Last week, I saw a nice dot...

0 0
Two good charts can use better titles

NPR has this chart, which I like: It's a small multiples of bumps charts. Nice, clear labels. No unnecessary things like axis labels. Intuitive organization by Major Factor, Minor Factor, and Not a Factor. Above all, the data convey a strong, surprising, message - despite many high-profile gun violence incidents this year, some Democratic voters are actually much less likely to see guns as a "major factor" in deciding their...

0 0
Headless people invade London, chart claims

Some 10 days ago, Mike B. on Twitter forwarded me this chart from Time Out: Mike added: "Wow, decapitations in London have really gone up!" A closer look at the chart reveals more problems. The axis labels are in the wrong places. It appears that the second dot represents 1940 and the second-last dot represents 2020. There are 12 dots between those two labels, corresponding to three evenly-spaced labels. This...

0 0
The downside of discouraging pie charts

It's no secret most dataviz experts do not like pie charts. Our disdain for pie charts causes people to look for alternatives. Sometimes, the alternative is worse. Witness: This chart comes from the Spring 2018 issue of On Investing, the magazine for Charles Schwab customers. It's not a pie chart. I'm forced to say the pie chart is preferred. The original chart fails the self-sufficiency test. Here is the 2007...

0 0
Is the chart answering your question? Excavating the excremental growth map

San Franciscans are fed up with excremental growth. Understandably. Here is how the Economist sees it - geographically speaking. *** In the Trifecta Checkup analysis, one of the questions to ask is "What does the visual say?" and with respect to the question being asked. The question is how much has the problem of human waste in SF grew from 2011 to 2017. What does the visual say? The number...

0 0
Two thousand five hundred ways to say the same thing

Wallethub published a credit card debt study, which includes the following map: Let's describe what's going on here. The map plots cities (N = 2,562) in the U.S. Each city is represented by a bubble. The color of the bubble ranges from purple to green, encoding the percentile ranking based on the amount of credit card debt that was paid down by consumers. Purple represents 1st percentile, the lowest amount...

0 0
Digital revolution in China: two visual takes

The following map accompanied an article in the Economist about China's drive to create a "digital silkroad," roughly defined as making a Silicon Valley.  The two variables plotted are the wealth of each province (measured by GDP per capita) and the level of Internet penetration. The designer made the following choices: GDP per capita is presented with less precision than Internet penetration. The former is grouped into five large categories...

0 0
Foodies say, add dataviz spice please

This Buzzfeed article proves that foodies love their food served with dataviz (tip: Chris P.). Menus are an undertapped resource when it comes to data visualization. There are several examples worth discussing. Venn diagrams are not easy to read, people. Plus they are hard to construct well... note the asymmetric areas. Here is one without circles: Then, I pared it down to its essence: *** This beer map is pretty...

0 0
This map steals story-telling from the designer

Stolen drugs is a problem at federal VA hospitals according to the following map. *** Let's evaluate this map from a Trifecta Checkup perspective. VISUAL - Pass by a whisker. The chosen visual form of a map is standard for geographic data although the map snatches story-telling from our claws, just as people steal drugs from hospitals. Looking at the map, it's not clear what the message is. Is there...

0 0
Light entertainment: I am a pen and I object

You've got to look out for conflicts on your dataviz! Example from Explosm courtesy of reader Chris P. Color says one thing. Face says something else. Words agree with Color. Pen objects.

0 0