RIP Bill van Zwet

The photograph above was taken by me at my summerhouse (i.e., an allotment garden with a comfortable large shed) in Leiden, exactly 9 years ago, with Jerry Friedman, Jacqueline Meulman, and Willem. It is early evening and we are enjoying a choice single malt and some tasty snacks. Jacqueline is wearing a t-shirt with the logo designed by me of our new master programme “Statistical Science for the Life and Behavioural Sciences”.

Below I am, for the time being, just posting a large collection of photographs sent in by a number of Bill’s old friends. I will also later add some of the comments they made in their emails. I will perhaps also add some personal remarks in the near future.

Before the many photo albums contributed by Bill’s friends, here is a link to a Zoom commemoration hosted by myself, which started one hour after the start of Willem’s funeral. Participants: Maryse Loranger, Richard Gill, Estate Khmaladze; Friedrich Götze and his wife, Marie-Colette van Lieshout, Nick Fisher; Peter Grunwald, and Ildar Ibragimov (who later managed to switch on his webcam); later arrivals were Ronald Cramer and Steffen Lauritzen:

https://www.math.leidenuniv.nl/~gill/zoom_0.mp4

The file is 207 MB mp4; duration 35 minutes; 5 minutes silence at ca. 25 – 30 min., when Zoom briefly fails us. You can also watch it on YouTube:

https://www.youtube.com/watch?v=s_yo1Uwzw9c.

And now to the photographs. First of all, three sets of pictures taken by Chris Klaassen, starting with Willem’s 75th birthday celebrations:

Chris Klaassen, Willems 80th birthday celebration, Leiden:

Chris Klaassen, Willem’s 80th birthday event in Utrecht:

David Mason:

Friedrich Götze:

Jacqueline Meulman and Maarten Kampert:

Marie Huskova:

Marta Fiocco:

Nick Fisher:

Niels Keiding:

© Niels Keiding

Peter Bickel:

Richard Gill:

Rudi Beran:

Sara van de Geer:

Stephen Stigler:

Vera Wellner:

Miscellaneous:

Today’s insights

I was going to write about some new insights here. I posted a picture. Then later added more pictures, to which I need a quick URL in order to refer to them elsewhere. So the new insights never came. But I think I still know what they were. Maybe I’ll write about them another time.

1000 points uniformly distributed on the sphere using the Archimedes theorem method (z is uniform [-1, +1]
https://www.phasespacecomputing.com/
2 “t-slices” of a uniform random sample (x, y, z, t) from S^3
Empirical historgram, and theoretical density of, t
“t-slices” of a uniform random sample (x, y, z, t) from S^3. N = 100 000. Delta t = 0.01. Red, radius 0.3. Blue, radius 0.8.
Histogram of x-coordinate of sample of ca. 52000 uniformly distributed points in 3-ball. Theoretical density = parabola. Also drawn: density of x-coordinate of uniformly dist points on 3-sphere = semicircle.
(x, y, z) coordinates of sample of size 1000 of uniform random points (x, y, z, t) on the 3-sphere.
1000 (x,y,z) points from uniform random sample of points (x,y,z,t) on 3-sphere.
Exit mobile version
%%footer%%