Axis
29 posts
Sneaky Pete via Twitter sent me the following chart, asking for guidance: This is a pretty standard dataset, frequently used in industry. It shows a breakdown of a company's profit by business unit, here classified by "state". The profit projection for the next year is measured on both absolute dollar terms and year-on-year growth. Since those two metrics have completely different scales, in both magnitude and unit, it is common...
A reader submitted the following chart from Pew Research for discussion. The reader complained that this chart was difficult to comprehend. What are some of the reasons? The use of color is superfluous. Each line is a "cohort" of people being tracked over time. Each cohort is given its own color or hue. But the color or hue does not signify much. The dotted lines. This design element requires a...
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...
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...
This post is part 2 of an appreciation of the chart project by Google Newslab, advised by Alberto Cairo, on the gender and racial diversity of the newsroom. Part 1 can be read here. In the previous discussion, I left out the following scatter bubble plot. This plot is available in two versions, one for gender and one for race. The key question being asked is whether the leadership in...
Laura pointed me to an infographic about tech worker salaries in major tech hubs (link). What's wrong with this map? The box "Global average" is doubly false. It is not global, and it is not the average! The only non-American cities included in this survey are Toronto, Paris and London. The only city with average salary above the "Global average" is San Francisco Bay Area. Since the Bay Area does...
I came across this chart on NYU's twitter feed. Growth has indeed been impressive; the dataviz less so. Here's the problem with not starting the vertical scale of a column chart at zero: In a column chart, the heights of the columns should be proportional to the data. Here they are misaligned because an equal amount has been chopped off below 30,000 from all columns. The light purple that I...
The above chart, when it was unveiled at the end of November last year, got some mileage on my Twitter feed so it got some attention. A reader, Eric N., didn't like it at all, and I think he has a point. Here are several debatable design decisions. The chart uses an inverted axis. A tax cut (negative growth) is shown on the right while a tax increase is shown...
If you are not sick of the Washington Post article about friends (not) letting friends join the other party, allow me to write yet another post on, gasp, that pie chart. And sorry to have kept reader Daniel L. waiting, as he pointed out, when submitting this chart to me, that he had tremendous difficulty understanding it: This is not one pie but six pies on a platter. There...
In the last post, I discussed one of the charts in the very nice Washington Post feature, delving into polarizing American voters. See the post here. (Thanks again Daniel L.) Today's post is inspired by the following chart (I am showing only the top of it - click here to see the entire chart): The chart plots each state as a separate row, so like most such charts, it is...