Archive for conference fees

ABC and ISBA in Edinburgh [early registration deadline]

Posted in Books, Mountains, pictures, Statistics, Travel, University life, Wines with tags , , , , , , , , , , , on April 6, 2018 by xi'an

Just a reminder that the deadline for early registration at ISBA 2018, and hence at the satellite workshop ABC in Edinburgh, since there is alas no separate access to the later, is drawing near! Given the already rather sharp rates of £380 for ISBA members and £250 at this time, and the incoming rise (to plummet at $1,1000 for registering on site!!), it would be advised to register prior to April 15, if you intend to attend…

(Disclaimer: I am not part of the organising committee of either event. And I have already written several posts here and there complaining on the absurd inflation of conference fees.)


3rd conference on geometric science[s] of information

Posted in Books, pictures, Statistics, Travel, University life with tags , , , , , , , , , , on January 31, 2017 by xi'an

A call for contribution to the 3rd Conference on Geometric Science of Information that I was asked to advertise. (I would have used Sciences instead of Science.) With a nice background picture related to Adelard de Bath, who among other things in natural philosophy introduced the Hindu-Arabic numerals in Europe [and later to America, even though the use of Arabic numerals there may soon come to an end]. And which Latin translation of Euclid’s Elements includes the above picture. The conference is on November 7-9, 2017, in the centre of Paris (Écoles de Mines, next to Luxembourg). (As I cannot spot the registration rates of that conference on the website, I cannot at this stage bring full support to the conference!)

ABC in Stockholm [on-board again]

Posted in Kids, pictures, Statistics, Travel, University life with tags , , , , , , , , , , , , , , , , on May 18, 2016 by xi'an

abcruiseAfter a smooth cruise from Helsinki to Stockholm, a glorious sunrise over the Ålend Islands, and a morning break for getting an hasty view of the city, ABC in Helsinki (a.k.a. ABCruise) resumed while still in Stockholm. The first talk was by Laurent Calvet about dynamic (state-space) models, when the likelihood is not available and replaced with a proximity between the observed and the simulated observables, at each discrete time in the series. The authors are using a proxy predictive for the incoming observable and derive an optimal—in a non-parametric sense—bandwidth based on this proxy. Michael Gutmann then gave a presentation that somewhat connected with his talk at ABC in Roma, and poster at NIPS 2014, about using Bayesian optimisation to reduce the rejections in ABC algorithms. Which means building a model of a discrepancy or distance by Bayesian optimisation. I definitely like this perspective as it reduces the simulation to one of a discrepancy (after a learning step). And does not require a threshold. Aki Vehtari expanded on this idea with a series of illustrations. A difficulty I have with the approach is the construction of the acquisition function… The last session while pretty late was definitely exciting with talks by Richard Wilkinson on surrogate or emulator models, which goes very much in a direction I support, namely that approximate models should be accepted on their own, by Julien Stoehr with clustering and machine learning tools to incorporate more summary statistics, and Tim Meeds who concluded with two (small) talks!, centred on the notion of deterministic algorithms that explicitly incorporate the random generators within the comparison, resulting in post-simulation recentering à la Beaumont et al. (2003), plus new advances with further incorporations of those random generators turned deterministic functions within variational Bayes inference

On Wednesday morning, we will land back in Helsinki and head back to our respective homes, after another exciting ABC in… workshop. I am terribly impressed by the way this workshop at sea operated, providing perfect opportunities for informal interactions and collaborations, without ever getting claustrophobic or dense. Enjoying very long days also helped. While it seems unlikely we can repeat this successful implementation, I hope we can aim at similar formats in the coming occurrences. Kitos paljon to our Finnish hosts!

ABC in Helsinki [on-board]

Posted in pictures, Statistics, Travel, University life with tags , , , , , , , , , , , , , , on May 17, 2016 by xi'an

abcruiseABC in Helsinki (a.k.a. ABCruise) has started! With a terrific weather most adequate for a cruise on the Baltic. The ship on which the workshop takes place is certainly larger than any I have been on, including the Channel ferries, and the inside alley looks rather like a shopping centre! However, the setting is exceptional, with comfy sea-facing cabins and pleasant breaks (including fancy tea!) Plus,  we have a quiet and cosy conference room that makes one forgets one is on a boat. Until it starts rocking. Or listing! The cruise boat is definitely large enough to be fairly stable. A unique experience we could consider for future (AB-see) workshops (with the caveat that we benefited from exceptional circumstances that brought the costs down to ridiculous amounts).

Richard Everitt talked about the synthetic likelihood approach and its connection with ABC. Making clear for me a point I had somewhat forgotten, namely that the approximative likelihood is a Gaussian at the observed summary statistics, but one centred at empirical moments derived from the simulation of pseudo summaries based on a given value of the parameter θ. So it is not an exact approach in that it does not converge to the true likelihood as the number of simulation grows to infinity. (While a kernel would converge.) That means it may (will) misrepresent the tails unless the distribution of the summary statistic is close to Normal. Richard also introduced bootstrap or bags of little bootstraps in order to speed up the generation of the pseudo-data, which makes sense albeit it moves the sampling away from the true model since it is conditional on  a single simulation.

Jean-Michel Marin introduced the ABC inference algorithm we are currently working on, using regression random forests that differ from the classification forests we used for model selection. (The paper is close to completion so I hope to be able to tell more in a near future!) Clara Grazian presented her semi-parametric work using ABC with Brunero Liseo. That was part of her thesis. Thomas Schön presented an extension of his particle Gibbs with adaptive sampling to the case of degenerate transitions, using an ABC approximation to get around this central problem. A very interesting entry that I need to study deeper. And Caroline Colijn talked about ABC for trees, mostly about the selection of summary statistics towards comparing tree topologies, with  a specific distance between trees that caters to the topology and only the topology.

ABC in Helsinki & Stockholm [deadline looming]

Posted in Kids, pictures, Statistics, Travel, University life with tags , , , , , , , , , , , , , on April 1, 2016 by xi'an

abcruiseIn case you have not yet registered for ABC in Helsinki (a.k.a. ABCruise), registration is open for just another week, with the all-inclusive fees of 200 euros for trip, cabin, talks, and meals! When registering you need to buy first a ticket on the Aalto University web shop: at some point, distinguishing between “Maksa” which means pay, and “Peruuta” which means cancel, may help! The submission of ABC posters is also encouraged till May 1, with emails to be sent to abcinhelsinki on gmail.

ABC in Helsinki & Stockholm [registration now open]

Posted in Kids, pictures, Statistics, Travel, University life with tags , , , , , , , , , , , , on February 22, 2016 by xi'an

abcruiseAs announced in earlier posts, ABC in Helsinki (a.k.a. ABCruise) will take place on May 16-18, 2016 on a regular cruise boat going from Helsinki, Finland,  on the 16th to Stockholm, Sweden, and back to Helsinki before noon on the 18th. The workshop takes place from noon on the 16th till noon on the 18th, with a short break around noon on the 17th in Stockholm. Registration is now open and the fees are an all-inclusive 200 euros for trip, cabin, and meals! Thanks to the organising committee for achieving such a bargain! Just do not wait for registering! The submission of posters is also encouraged, with emails to be sent to abcinhelsinki on gmail.

another borderline conference

Posted in Kids, University life with tags , , , , , , on June 25, 2015 by xi'an

Following yesterday’s surprise at the unpleasant conference business run by WASET, I was once again confronted today with conference fees that sound like an unacceptable siphoning of research funds and public money. One of my PhD students got earlier personally invited to present a talk at EUSIPCO 2015, a European signal processing conference taking place in Nice next September and she accepted the invitation. Now, contrary to yesterday’s example, this EUSIPCO 2015 is a genuine conference sponsored by several European signal processing societies. From what I understand, speakers and poster presenters must submit papers that are reviewed and then published in the conference proceedings, part of the IEEE Xplore on-line digital library (impact factor of 0.04). As the conference is drawing near, my student is asked to register and is “reminded” of small prints in the conference rules, namely that “at least one author per paper must register by June 19, 2015 at the full rate”, student or not student, which means a 300€ difference in the fees and has absolutely no justification whatsoever since the papers are only processed electronically…

eupiscoI checked across a few of the past editions of EUSIPCO and the same rip-off rule applies to those as well. I see no rational explanation for this rule that sounds like highway robbery and leads to the de facto exclusion of students from conferences… In fine, my student withdrew her paper and participation at EUSIPCO.