Archive for gather.town

ISBA 2021.3

Posted in Kids, Mountains, pictures, Running, Statistics, Travel, University life, Wines with tags , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , on July 1, 2021 by xi'an

Now on the third day which again started early with a 100% local j-ISBA session. (After a group run to and around Mont Puget, my first real run since 2020!!!) With a second round of talks by junior researchers from master to postdoc level. Again well-attended. A talk about Bayesian non-parametric sequential taxinomy by Alessandro Zito used the BayesANT acronym, which reminded me of the new vave group Adam and the Ants I was listening to forty years ago, in case they need a song as well as a logo! (Note that BayesANT is also used for a robot using Bayesian optimisation!) And more generally a wide variety in the themes. Thanks to the j-organisers of this 100% live session!

The next session was on PDMPs, which I helped organise, with Manon Michel speaking from Marseille, exploiting the symmetry around the gradient, which is distribution-free! Then, remotely, Kengo Kamatani, speaking from Tokyo, who expanded the high-dimensional scaling limit to the Zig-Zag sampler, exhibiting an argument against small refreshment rates, and Murray Pollock, from Newcastle, who exposed quite clearly the working principles of the Restore algorithm, including why coupling from the past was available in this setting. A well-attended session despite the early hour (in the USA).

Another session of interest for me [which I attended by myself as everyone else was at lunch in CIRM!] was the contributed C16 on variational and scalable inference that included a talk on hierarchical Monte Carlo fusion (with my friends Gareth and Murray as co-authors), Darren’s call to adopt functional programming in order to save Bayesian computing from extinction, normalising flows for modularisation, and Dennis’ adversarial solutions for Bayesian design, avoiding the computation of the evidence.

Wes Johnson’s lecture was about stories with setting prior distributions based on experts’ opinions. Which reminded me of the short paper Kaniav Kamary and myself wrote about ten years ago, in response to a paper on the topic in the American Statistician. And could not understand the discrepancy between two Bayes factors based on Normal versus Cauchy priors, until I was told they were mistakenly used repeatedly.

Rushing out of dinner, I attended both the non-parametric session (live with Marta and Antonio!) and the high-dimension computational session on Bayesian model choice (mute!). A bit of a schizophrenic moment, but allowing to get a rough picture in both areas. At once. Including an adaptive MCMC scheme for selecting models by Jim Griffin. Which could be run directly over the model space. With my ever-going wondering at the meaning of neighbour models.

ISBA 20.2.21

Posted in Kids, Mountains, pictures, Running, Statistics, Travel, University life, Wines with tags , , , , , , , , , , , , , , , , , , , , , , , , , , , on June 30, 2021 by xi'an

A second day which started earlier and more smoothly with a 100% local j-ISBA session. (Not counting the invigorating swim in Morgiou!) With talks by junior researchers from master to postdoc level, as this ISBA mirror meeting was primarily designed for them, so that they could all present their work, towards gaining more visibility for their research and facilitating more interactions with the participants. CIRM also insisted on this aspect of the workshop, which was well-attended.

I alas had to skip the poster session [and the joys of gather.town] despite skipping lunch [BND], due to organisational constraints. Then attended the Approximate Bayesian computation section, including one talk by Geoff Nicholls on confidence estimation for ABC, following upon the talk given by Kate last evening. And one by Florian Maire on learning the bound in accept-reject algorithms on the go, as in Caffo et al. (2002), which I found quite exciting and opening new possibilities, esp. if the Markov chain thus produced can be recycled towards unbiasedness without getting the constant right! For instance, by Rao-Blackwellisation, multiple mixtures, black box importance sampling, whatever. (This also reminded me of the earlier Goffinet et al. 1996.)

Followed by another Bayesian (modeling and) computation session. With my old friend Peter Müller talking about mixture inference with dependent priors (and a saturated colour scheme!), Matteo Ruggieri [who could not make it to CIRM!] on computable Bayesian inference for HMMs. Providing an impressive improvement upon particle filters for approximating the evidence. Also bringing the most realistic Chinese restaurant with conveyor belt! And Ming Yuan Zhou using optimal transport to define distance between distributions. With two different conditional distributions depending on which marginal is first fixed. And a connection with GANs (of course!).

And it was great to watch and listen to my friend Alicia Carriquiry talking on forensic statistics and the case for (or not?!) Bayes factors. And remembering Dennis Lindley. And my friend Jim Berger on frequentism versus Bayes! Consistency seems innocuous as most Bayes procedures are. Empirical coverage is another kind of consistency, isn’t it?

A remark I made when re-typing the program for CIRM is that there are surprisingly few talks about COVID-19 overall, maybe due to the program being mostly set for ISBA 2020 in Kunming. Maybe because we are more cautious than the competition…?!

And, at last, despite a higher density of boars around the CIRM facilities, no one got hurt yesterday! Unless one counts the impact of the French defeat at the Euro 2021 on the football fans here…

ISBA 2.1…0!

Posted in Statistics, University life with tags , , , , , , , on June 28, 2021 by xi'an

As the first fully virtual ISBA 2021 meeting is about to start, let me remind participants of the following:

On the Whova Agenda, you can see the Agenda in your local time, be sure to toggle the option. And the list of posters for each of the four poster sessions is available in the Agenda, as well as at the entrance of each poster “room” on gather.town

Reminder for session chairs

  •  Please join your session via Zoom’s panelist link instead of Whova
  • Please monitor Zoom’s Q&A and Zoom’s chat for questions from attendees
  • Please monitor the session time and remind the speakers of their time, as the webinar will close after 3 minutes after the end of the session
  • Please keep to the planned schedule for each talk in case of a missing speaker or of a speaker unable to join the Zoom platform for connection or technical reasons

Reminder for speakers

  • Please join your session via Zoom’s panelist link instead of Whova

Reminder for the remaining 2136 attendees

  • The Zoom link for a given session is available by selection this session from Whova Agenda and clicking on “Join the live stream here”
  • Please type your questions using Zoom’s Q&A or Zoom’s chat, and specify which speaker’s name you would like to hear the answers from
  • Please do not use Whova’s chat for questions  
  • Contributed sessions are recorded and already available, while invited sessions will be recorded with permission from the speakers

ISBA 2021, one more week but already in the future!

Posted in pictures, Statistics, Travel, University life with tags , , , , , , , , , on June 21, 2021 by xi'an


The main section of the ISBA 2021 (formerly ISBA 2020) conference starts a week from today, with short courses this week, but it is now a futuristic conference in that… the number of registered participants already exceeds the year of the meeting! There are currently 2033 registrations, a quantic leap from the earlier editions (if helped with the virtual nature of the meeting and the absence of any registration fee). Here are the recommendations to be found on the Whova conference portal, just in case:

The ISBA conference will be a mixture of live talks, pre-recorded talks, and posters. All live-streaming will be via Zoom, with links integrated into the Whova platform.

    1. Plenary talks (i.e., Foundational Lectures, Keynote Lectures, and Named Lectures) and all invited talks will be live-streamed during the corresponding sessions.
    2. Contributed talks are prerecorded (available from June 10, 2021). During the live-streamed Contributed Sessions, each speaker will give a 5-min live recap of their contributed talk,  highlighting the main points, followed by live discussion and Q&A from the audience.
    3. Contributed speakers who had optionally chosen to accompany their talk with a poster will present the poster in their designated Poster Sessions. All Poster Sessions will be held on Gather.town, which will also serve as the virtual space for social times during the whole conference.
    4. Gather.town is live at https://gather.town/app/QZTh2a4InnLxAvYF/ISBA_WM_2021_main. You should be able to access with the same email used to register for Whova.

And be aware that the schedule page does not contain the links to the prerecorded videos and slides. Make sure to use the webapp link.

practical details on ISBA²⁰²¹

Posted in Statistics, University life with tags , , , , , , , , on May 31, 2021 by xi'an

Remember that the [online]  ISBA 2021 conference will be a mixture of live talks, pre-recorded talks, and posters. All live-streaming will be via Zoom, with links integrated into the Whova platform.

  1. Plenary talks (i.e., Foundational Lectures, Keynote Lectures, and Named Lectures) and all invited talks will be live-streamed during the corresponding sessions.
  2. Contributed talks are prerecorded (available from June 10, 2021). During the live-streamed Contributed Sessions, each speaker will give a 5-min live recap of their contributed talk,  highlighting the main points, followed by live discussion and Q&A from the audience.
  3. Contributed speakers who had optionally chosen to accompany their talk with a poster will present the poster [live] in their designated Poster Sessions. All Poster Sessions will be held on Gather.town, which will also serve as the virtual space for social times during the whole conference.
  4. One week before the conference, Gather.town will go live and all posters will also become available then.
  5. Speakers of all talk types will have the option to upload and post their slides on Whova starting one week before the conference [which I personally recommend as I find it too easy for my attention to drift off during an online and need to recheck earlier slides to reconnect!]