covid-19

148 posts
Visually displaying multipliers

As I'm preparing a blog about another real-world study of Covid-19 vaccines, I came across the following chart (the chart title is mine). As background, this is the trend in Covid-19 cases in the U.K. in the last couple of months, courtesy of OurWorldinData.org. The React-1 Study sends swab kits to randomly selected people in England in order to assess the prevalence of Covid-19. Every month, there is a new...

0 0
Working hard at clarity

As I am preparing another blog post about the pandemic, I came across the following data graphic, recently produced by the CDC for a vaccine advisory board meeting: This is not an example of effective visual communications. *** For one thing, readers are directed to scour the footnotes to figure out what's going on. If we ignore those for the moment, we see clusters of bubbles that have remained pretty...

0 0
Simple charts are the hardest to do right

The CDC website has a variety of data graphics about many topics, one of which is U.S. vaccinations. I was looking for information about Covid-19 data broken down by age groups, and that's when I landed on these charts (link). The left panel shows people with at least one dose, and the right panel shows those who are "fully vaccinated." This simple chart takes an unreasonable amount of time to...

0 0
Check your presumptions while you’re reading this chart about Israel’s vaccination campaign

On July 30, Israel began administering third doses of mRNA vaccines to targeted groups of people. This decision was controversial since there is no science to support it. The policymakers do have educated guesses by experts based on best-available information. By science, I mean actual evidence. Since no one has previously been given three shots, there can be no data on which anyone can root such a decision. Nevertheless, the...

0 0
What metaphors give, they take away

Aleks pointed me to the following graphic making the rounds on Twitter: It's being passed around as an example of great dataviz. The entire attraction rests on a risque metaphor. The designer is illustrating a claim that Covid-19 causes erectile dysfunction in men. That's a well-formed question so in using the Trifecta Checkup, that's a pass on the Q corner. What about the visual metaphor? I advise people to think...

0 0
Hanging things on your charts

The Financial Times published the following chart that shows the rollout of vaccines in the U.K. (I can't find the online link to the article. The article is titled "AstraZeneca and Oxford face setbacks and success as battle enters next phase", May 29/30 2021.) This chart form is known as a "streamgraph", and it is a stacked area chart in disguise.  The same trick can be applied to a column...

0 0
Did prices go up or down? Depends on how one looks at the data

The U.S. media have been flooded with reports of runaway inflation recently, and it's refreshing to see a nice article in the Wall Street Journal that takes a second look at the data. Because as my readers know, raw data can be incredibly deceptive. Inflation typically describes the change in price level relative to the prior year. The month-on-month change in price levels is a simple seasonal adjustment used to...

0 0
Plotting the signal or the noise

Antonio alerted me to the following graphic that appeared in the Economist. This is a playful (?) attempt to draw attention to racism in the game of football (soccer). The analyst proposed that non-white players have played better in stadiums without fans due to Covid19 in 2020 because they have not been distracted by racist abuse from fans, using Italy's Serie A as the case study. The chart struggles to...

0 0
Probabilities and proportions: which one is the chart showing

The New York Times showed this chart (link): My first read: oh my gosh, 40-50% of the unvaccinated Americans are living their normal lives - dining at restaurants, assembling with more than 10 people, going to religious gatherings. After reading the text around this chart, I realize I have misinterpreted it. The chart should be read by columns. Each column is a "pie chart". For example, the first column shows...

0 0
Pies, bars and self-sufficiency

Andy Cotgreave asked Twitter followers to pick between pie charts and bar charts: The underlying data are proportions of people who say they won't get the coronavirus vaccine. I noticed two somewhat unusual features: the use of pies to show single proportions, and the aspect ratio of the bars (taller than typical). Which version is easier to understand? To answer this question, I like to apply a self-sufficiency test. This...

0 0