Embrace me, surround me as the rush comes.drift deeper into the soundmore quotes

Scientific graphical abstracts — design guidelines

# visualization + design

81 digits of $\pi$ as a forest of trees: standard, bat cave and underwater editions. ( BUY ARTWORK )
The 2021 Pi Day art celebrates the digits of $\pi$ with a forest! Visit the bat cave and underwater ecosystems for the full experience.

# $\pi$ Day 2020 Art — Digits, poetically.

2021 $\pi$ reminds us that good things grow for those who wait.' edition.
2019 $\pi$ has hundreds of digits, hundreds of languages and a special kids' edition.
2018 $\pi$ day stitches street maps into new destinations.
2017 $\pi$ day imagines the sky in a new way.

2016 $\pi$ approximation day wonders what would happen if about right was right.
2016 $\pi$ day sees digits really fall for each other.
2015 $\pi$ day maps transcendentally.
2014 $\pi$ approx day spirals into roughness.

2014 $\pi$ day hypnotizes you into looking.
2014 $\pi$ day
2013 $\pi$ day is where it started
Circular $\pi$ art and other distractions

On March 14th celebrate $\pi$ Day. Hug $\pi$—find a way to do it.

For those who favour $\tau=2\pi$ will have to postpone celebrations until July 26th. That's what you get for thinking that $\pi$ is wrong. I sympathize with this position and have $\tau$ day art too!

If you're not into details, you may opt to party on July 22nd, which is $\pi$ approximation day ($\pi$ ≈ 22/7). It's 20% more accurate that the official $\pi$ day!

Finally, if you believe that $\pi = 3$, you should read why $\pi$ is not equal to 3.

Most of the art is available for purchase as framed prints and, yes, even pillows. Sleep's never been more important — I take custom requests.
3 Little $\pi$,
1 what
4 can you tell us?

Welcome to this year's celebration of $\pi$ and mathematics. Among the chaos of CORVID-19, this year $\pi$ Day celebrations are short poetic emissions I call “piku” . They are brief pauses for the time.

Start by reading how piku are constructed and then browse submitted piku. Consider participating by submitting your own piku. All you need is a pen and a few (small) words. Very therapeutic.

But if the words here don't help, immerse yourself in my coronavirus art. It's quite catching.

If you enjoy poetry and words, see how I convert spam into poems in the style of ee cummings and if you like to see words arrange on page, look through my typographic art.

## $\pi$ day — poetically

What does this poem have to do with $\pi$ day?

3 A Three and
1 a
4 one and a four.

Or this one?

1 Dust
4 in space vacuum
0
3 clogs alien
2 machines.
0
2 Bummer.
0

These are all nku (details and definitions). Like a haiku, an nku is a poem whose structure (line and syllable count) is constrained by the digits in some number $n$.

The first poem above is a piku ($\pi$ku, パイク), based on the first three digits of $\pi$. The second poem above is the nku for the date of this year's celebration 14032020.

Even $\pi$ approximation day 22/7 has its own nku.

2 Roughly
2 the same
7 is frequently good enough.

Those that believe in the power of the Tau manifesto ($\tau = 2 \pi$) can create “tauku” .

6 Two times by anyone
2 equals
8 one time by anytwo, I hope.

I celebrate Tau day with equal, not double, enthusiasm and have made Tau day art.

If you would like to contribute to this year's piku celebration, email me a piku with "PIKU:" in subject line. Or, tweet it with the $#piku$ hashtag.

3 piku are
1 not
4 hard to write but
1 good
5 ones are not easy.

# Happy 2021 $\pi$ Day—A forest of digits

Sun 14-03-2021

Celebrate $\pi$ Day (March 14th) and finally see the digits through the forest.

The 26th tree in the digit forest of $\pi$. Why is there a flower on the ground?. (details)

This year is full of botanical whimsy. A Lindenmayer system forest – deterministic but always changing. Feel free to stop and pick the flowers from the ground.

The first 46 digits of $\pi$ in 8 trees. There are so many more. (details)

And things can get crazy in the forest.

A forest of the digits of '\pi$, by ecosystem. (details) Check out art from previous years: 2013$\pi$Day and 2014$\pi$Day, 2015$\pi$Day, 2016$\pi$Day, 2017$\pi$Day, 2018$\pi$Day and 2019$\pi` Day.

# Testing for rare conditions

Tue 16-03-2021

All that glitters is not gold. —W. Shakespeare

The sensitivity and specificity of a test do not necessarily correspond to its error rate. This becomes critically important when testing for a rare condition — a test with 99% sensitivity and specificity has an even chance of being wrong when the condition prevalence is 1%.

We discuss the positive predictive value (PPV) and how practices such as screen can increase it.

Nature Methods Points of Significance column: Testing for rare conditions. (read)

Altman, N. & Krzywinski, M. (2021) Points of significance: Testing for rare conditions. Nature Methods 18

# Standardization fallacy

Tue 09-02-2021

We demand rigidly defined areas of doubt and uncertainty! —D. Adams

A popular notion about experiments is that it's good to keep variability in subjects low to limit the influence of confounding factors. This is called standardization.

Unfortunately, although standardization increases power, it can induce unrealistically low variability and lead to results that do not generalize to the population of interest. And, in fact, may be irreproducible.

Nature Methods Points of Significance column: Standardization fallacy. (read)

Not paying attention to these details and thinking (or hoping) that standardization is always good is the "standardization fallacy". In this column, we look at how standardization can be balanced with heterogenization to avoid this thorny issue.

Voelkl, B., Würbel, H., Krzywinski, M. & Altman, N. (2021) Points of significance: Standardization fallacy. Nature Methods 18:5–6.

# Graphical Abstract Design Guidelines

Fri 13-11-2020

Clear, concise, legible and compelling.

Making a scientific graphical abstract? Refer to my practical design guidelines and redesign examples to improve organization, design and clarity of your graphical abstracts.

Graphical Abstract Design Guidelines — Clear, concise, legible and compelling.

# "This data might give you a migrane"

Tue 06-10-2020

An in-depth look at my process of reacting to a bad figure — how I design a poster and tell data stories.

A poster of high BMI and obesity prevalence for 185 countries.

# He said, he said — a word analysis of the 2020 Presidential Debates

Thu 01-10-2020

Building on the method I used to analyze the 2008, 2012 and 2016 U.S. Presidential and Vice Presidential debates, I explore word usagein the 2020 Debates between Donald Trump and Joe Biden.

Analysis of word usage by parts of speech for Trump and Biden reveals insight into each candidate.