Here we are now at the middle of the fourth large part of this talk. • Pepe Deluxe • get nowhere • more quotes
very clickable
visualization + math

π Day 2026 Art Posters - Art for the 5%
 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca buy artwork
▲ 2026 π DAY | Art for the 5%: digits of `\pi` hidden in plain view. Here, the symbol `\pi` is encoded. (explore the art, BUY ARTWORK)

π Day 2026 Art Posters - Art for the 5%
 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca buy artwork
▲ 2026 π DAY | Art for the 5%: digits of `\pi` hidden in plain view. Here the first 9 digits of `\pi` (314 159 265) are encoded. (explore the art, BUY ARTWORK)

`\pi` Day 2020 Art — Digits, poetically.


Pi Day 2020 Art - Digits, poetically.
 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ 2026 π DAY | Art for the 5%.

Pi Day 2020 Art - Digits, poetically.
 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ 2025 π DAY | TTCAGT: A sequence of digits.

Pi Day 2020 Art - Digits, poetically.
 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ 2024 π DAY | Explore the garden of digits.

Pi Day 2020 Art - Digits, poetically.
 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ 2023 π DAY | Repeated sequence


Pi Day 2020 Art - Digits, poetically.
 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ 2022 π DAY | three one four: a number of digits

Pi Day 2020 Art - Digits, poetically.
 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ 2021 π DAY | Good things grow for those who wait.' edition.

Pi Day 2020 Art - Digits, poetically.
 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ 2020 π DAY | The piku.

Pi Day 2020 Art - Digits, poetically.
 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ 2019 π DAY | Hundreds of digits, hundreds of languages and a special kids' edition.


Pi Day 2020 Art - Digits, poetically.
 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ 2018 π DAY | Street maps to new destinations.

Pi Day 2020 Art - Digits, poetically.
 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ 2017 π DAY | Imagine the sky in a new way.

Pi Day 2020 Art - Digits, poetically.
 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ 2016 π APPROXIMATION DAY | What would happen if about right was right.

Pi Day 2020 Art - Digits, poetically.
 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ 2016 π DAY | These digits really fall for each other.


Pi Day 2020 Art - Digits, poetically.
 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ 2015 π DAY | A transcendental experience.

Pi Day 2020 Art - Digits, poetically.
 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ 2014 π APPROXIMATION DAY | Spirals into roughness.

Pi Day 2020 Art - Digits, poetically.
 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ 2014 π DAY | Hypnotizes you into looking.

Pi Day 2020 Art - Digits, poetically.
 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ 2014 π DAY | Come into the fold.


Pi Day 2020 Art - Digits, poetically.
 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ 2013 π DAY | Where it started.

Pi Day 2020 Art - Digits, poetically.
 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ CIRCULAR π 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 COVID-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.

The music video Transcendental Tree Map premieres on 2020 Pi Day.

The music is from Max Cooper's Yearning for the Infinite album. Animation by me and Nick Cobby. Read the details about the video.

music video

▲ “Transcendental Tree Map” from Yearning for the Infinite. Music by Max Cooper. Animation by Nick Cobby and myself.

live performance at Barbican Centre

▲ “Transcendental Tree Map” live at the album's premiere at the Barbican Hall in London. Learn about the album.

Pi Day 2020 Art - Digits, poetically.
 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca buy artwork
▲ 20,244 digits of `\pi` in a 7 level treemap. Variable line thickness. This is the image that was the basis for Max Cooper's Transcendental Area Map track on the Yearning for Infinity album. (zoom, BUY ARTWORK)
news + thoughts

Chromosomes — music, genomes, split-flaps

Wed 14-10-2026

A short electronic music concert based on structures of chromosomes 21, Y and 1.

Each track uses a microtonal scale derived from the cytogenetic band positions of the chromosome. Rhythms are based on relative lengths of cytogenetic bands.

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ CHROMOSOMES | Genomes, split-flaps, music. (watch)
music
Gregory Coles
voice
Hannah Iqbal
concept & animation
Martin Krzywinski
thanks to
John Dupuis

Consequences of missing data

Fri 04-09-2026

Either I've been missing something or nothing has been going on. —Karen Elizabeth Gordon

Missing data are everywhere. Subjects may decline to participate in a survey or fail to answer sensitive questions. A cell culture might fail due to contamination. Instrument failures or mishandling of a sample may lead to missing observations. But why are missing data a problem?

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ Nature Methods Points of Significance column: Consequences of missing data. (read)

This month, we begin a series of articles about practical and statistical aspects of missing data. We'll see that missing data can increase variability and introduce bias and we will ask whether anything can be done to mitigate these consequences. It turns out that, in the case where we know nothing about the missing subjects, no mitigation is possible. We must accept higher variability and, if we have a suspicion that the missing subjects aren’t completely random, possible bias as well.

Tanujit Dey, T., Lipsitz, S.R., Fitzmaurice, G., Krzywinski, M. & Altman, N. (2026) Points of significance: Consequences of missing data. Nat. Methods 23:1661–1663.

Double Robustness

Mon 04-05-2026

It is not certain that everything is uncertain. —Blaise Pascal

We have already explored how we can mitigate bias caused by confounding variables in observational studies using propensity score (PS) matching (PSM) and propensity score weighting (PSW). However, any statistical model is only as good as its assumptions and, if it is specified incorrectly, it can itself produce biased estimates of the treatment effect.

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ Nature Methods Points of Significance column: Double Robustness. (read)

This month, we explore double robustness, a powerful statistical concept that provides a valuable “safety net” against the risk of an incorrect model. It offers two opportunities, instead of just one, to obtain a valid estimate of the treatment effect — making it possible to draw credible causal inferences from observational data without having to depend on a single set of modeling assumptions.

Kurz, C.F., Krzywinski, M. & Altman, N. (2026) Points of significance: Double Robustness. Nat. Methods 23:868–869.

Nature Biotechnology cover

Thu 23-04-2026

My cover design on the 7 April 2026 Nature Biotechnology issue shows the dendrogram that represents a cluster of uniquely expressed (or downregulated) genes in human naive stem cells induced from such cells. Within each dendrogram block, the genomic barcode sequence (sampled from Supplementary Table 1) is depicted with a Code 39 barcode. The highlighted barcode is one of those used for cell isolation.

Ishiguro S. et al. A multi-kingdom genetic barcoding system for precise clone isolation (2026) Nature Biotechnology 44:616–629.

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ My Nature Biotechnology phylogenetic tree cover (volume 44, issue 4, 7 April 2026). (more)

Browse my gallery of cover designs.

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ A catalogue of my journal and magazine cover designs. (more)

Happy 2026 π Day—
Art for the 5%

Fri 13-03-2026

Celebrate π Day (March 14th) and enjoy the art — but only if you're part of the 5%.

Go ahead, see what you can't see.

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ 2026 π DAY | Art for the 5%. Shown in the style of Ishihara color test plates, the art is visible only to those with colour blindness. (details)

Ishihara's Tests for Colour Deficiency

Sun 08-03-2026

Authentic and accurate images of Ishihara's test plates photographed (and lovingly color-corrected) from the 38-plate Ishihara's Tests for Colour Deficiency.

I also provide the position, size, and color of each circle on each test plate.

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ ISHIHARA'S TEST PLATE 6 | This plate is part of the set of transformation plates. If you see 5, you're ok. If you see 2, you're not. (details)
Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
▲ ISHIHARA'S TEST PLATE 18 | This plate is part of the set of mysterious hidden plates. If you don't see anything, you're ok. If you see 5, you're not. (details)
Martin Krzywinski | contact | Canada's Michael Smith Genome Sciences Centre ⊂ PHSA
Google whack “vicissitudinal corporealization”