In volunteer computing systems the users get to decide when, and how much, their own computers are going to be working in a particular problem. We have been working for some time in using volunteer computing for evolutionary algorithms, and all our efforts have focused in having a scalable back end and also finding how the user behaves in order to understand the behavior. A priori, one would think that the more users, the better. However, the fact that these systems are asynchronous and have heterogeneous capabilities means that it might happen that new users do not really have any contribution to the overall effort.
In this paper presented at the EvoStar conference this week, we took a different approach to analyzing performance by using compression entropy, computed over the number of contributions per minute. The bigger compression, the more uniform contributions are; the lower the compression, that means that the contributions change all the time. After some preliminary reports published in FigShare we found that there is a clear trend in an increasing entropy making the algorithm end much faster. This contradicts our initial guess, and also opens new avenues for the design of volunteer evolutionary computing systems, and probably other systems whose performande depends on diversity such as evolutionary algorithms.
Check out the poster and also the presentation done at the conference. You will miss, however, the tulip origami we gave out to the visitors of the poster.
In our research group we support open science, that is why you can find everything, from data to processing scripts to the sources of this paper, in the GitHub repository
As an initiative to keep an implementation of the recent nature-inspired metaheuristics as well as the classical ones in a single open source framework, we introduce EvoloPy. EvoloPy is an open source and cross-platform Python framework that implements a wide range of metaheuristic algorithms. The goal is to take the advantage of the rapidly growing scientific community of Python and provide a set of robust optimizers as free and open source software. We believe that implementing such algorithms in Python will increase their popularity and portability among researchers and non-specialists coming from different domains. The powerful libraries and packages available in Python (such as NumPy) will make it more feasible to apply metaheuristics for solving complex problems on a much higher scale.
Our poster of EvoloPy was accepted in the ECTA conference and we recently presented it in Porto. Have a look at the paper and poster source:
Paper source: https://github.com/7ossam81/EvoloPy
Poster source: https://github.com/7ossam81/EvoloPy-poster
List of available optimizers: https://github.com/7ossam81/EvoloPy/wiki/List-of-optimizers
Thank you Python and NumPy :)
Our poster was accepted in the ECTA conference and we recently presented it in Porto. Have a look at the paper and poster source https://github.com/geneura-papers/2016-ea-languages-PPSN/releases/tag/v1.0ECTA that uses Knitr, and check out the poster.
The cloud is where you run your applications, but it’s also how you will design your algorithms from now on. Evolutionary algorithms are specially suited for this, and that is why I have given tutorials on how to adapt evolutionary algorithms to the cloud in PPSN and lately, when one of the keynotes dropped, an updated and abridged version at ECTA 16.
In these tutorials I make an introduction to what is the cloud and what it means: basically, create applications as loosely connected, polyglot, multi-vendor sets of different programs. Which will spawn a slew of new algorithms, starting with the pool-based evolutionary algorithm we have working on for so long.
This September we attended to the IEEE CIG 2017 Conference in Santorini, Greece, to present the paper “Evolutionary Deckbuilding in HearthStone”. This paper was written in collaboration with our colleagues Alberto Tonda and Giovanni Squillero.
The story of this paper started a (not so) long time ago while me and Alberto were discussing about how awesome HearthStone is. Suddenly, we thought about how easy it would be to create the constraints for the uGP framework, and that there were some open source simulators of the game. In a while, we already had the constraints, the simulator adapted to accept individuals from uGP, and some experiments running.
And we finished the paper after, of course.
You can download the paper draft from here (the electronic original version is not available yet).
And here is the presentation:
—One of the most notable features of collectible card games is deckbuilding, that is, defining a personalized deck before the real game. Deckbuilding is a challenge that involves a big and rugged search space, with different and unpredictable behaviour
after simple card changes and even hidden information. In this paper, we explore the possibility of automated deckbuilding: a genetic algorithm is applied to the task, with the evaluation delegated to a game simulator that tests every potential deck against a varied and representative range of human-made decks.
In these preliminary experiments, the approach has proven able to create quite effective decks, a promising result that proves that, even in this challenging environment, evolutionary algorithms can find good solutions.
Algunos enlaces que se han comentado:
As we usually do, we attended GECCO 2016 this year, a genetic and evolutionary algorithm confernce which took place in Denver, in America.
The paper accepted in the Parallel Evolutionary Systems session and two papers presented in workshops dealt with pool-based evolutionary algorithms and their implementation in volunteer computer systems in browsers. Unlike mainstream evolutionary algorithms, which put the algorithm and the population in the same process or thread, pool based evolutionary algorithms decouple population from algorithms, allowing these to work ephemerally, spontaneously and in a completely asynchronous way.
How Can we Make the User more Efficient in Interactive Evolutionary Algorithms?, which was an exposition of how what the web page shows has a clear influence on the time the user spends in it and thus on the performance of the system, and also a call for help from this visualization workshop on how to make this time as long as possible. We received many helpful comments, including using badges for users (how this could be done without authentication, which would be a barrier, is not so easy to work out) or creating leaderboards so users can compete with each other.
The paper presented in GECCO proper entitled Performance for the masses
Experiments with A Web Based Architecture to Harness Volunteer Resources for Low Cost Distributed Evolutionary Computation, dealt with a series of experiments using the platform NodIO published in OpenShift. It has actually been running continuously for a year, although the number of volunteers is close to 0. I will have to check it out, anyway, this long term behavior would be interesting. The paper presented how the behavior of the user presents some patterns, including the fact that their contributions follow a Weibull distribution, very close to what happens in games. Which, in fact is what lead us to submit the first paper to the visualization workshop.
As usual, all our papers are open source and reside in GitHub. If you want copies, just leave a comment and we’ll email them to you.