Dot plot

43 posts
Measles babies

Mona Chalabi has made this remarkable graphic to illustrate the effect of the anti-vaccine movement on measles cases in the U.S.: As a form of agitprop, the graphic seizes upon the fear engendered by the defacing red rash of the disease. And it's very effective in articulating its social message. *** I wasn't able to find the data except for a specific year or two. So, this post is more...

0 0
Seeking simplicity in complex data: Bloomberg’s dataviz on UK gender pay gap

Bloomberg featured a thought-provoking dataviz that illustrates the pay gap by gender in the U.K. The dataset underlying this effort is complex, and the designers did a good job simplifying the data for ease of comprehension. U.K. companies are required to submit data on salaries and bonuses by gender, and by pay quartiles. The dataset is incomplete, since some companies are slow to report, and the analyst decided not to...

0 0
The Economist on the Economist: must read now

A visual data journalist at the Economist takes a critical eye on charts published by the Economist (link). This is a must read! (Hat tip: Fernando) Here are some of my commentary on past Economist charts.

0 0
Is the visual serving the question?

The following chart concerns California's bullet train project. Now, look at the bubble chart at the bottom. Here it is - with all the data except the first number removed: It is impossible to know how fast the four other train systems run after I removed the numbers. The only way a reader can comprehend this chart is to read the data inside the bubbles. This chart fails the "self-sufficiency...

0 0
Two views of earthquake occurrence in the Bay Area

This article has a nice description of earthquake occurrence in the San Francisco Bay Area. A few quantities are of interest: when the next quake occurs, the size of the quake, the epicenter of the quake, etc. The data graphic included in the article fails the self-sufficiency test: the only way to read this chart is to read out the entire data set - in other words, the graphical details...

0 0
Big Macs in Switzerland are amazing, according to my friend

Note for those in or near Zurich: I'm giving a Keynote Speech tomorrow morning at the Swiss Statistics Meeting (link). Here is the abstract: The best and the worst of data visualization share something in common: these graphics provoke emotions. In this talk, I connect the emotional response of readers of data graphics to the design choices made by their creators. Using a plethora of examples, collected over a dozen...

0 0
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
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
Common charting issues related to connecting lines, labels, sequencing

The following chart about "ranges and trends for digital marketing salaries" has some problems that appear in a great number of charts. The head tilt required to read the job titles. The order of the job titles is baffling. It's neither alphabetical nor by salary. The visual form suggests that we could see trends in salaries reading left-right, but the only information about trends is the year on year salary...

0 0