Propensity score weighting

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.

▲ 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

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.

▲ My Nature Biotechnology phylogenetic tree cover (volume 44, issue 4, 7 April 2026). (more)

Browse my gallery of cover designs.

▲ A catalogue of my journal and magazine cover designs. (more)

Happy 2026 π Day—
Art for the 5%

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.

▲ 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

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.

▲ 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)

▲ 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)