Evolutionary model trees for handling continuous classes in machine learning

Model trees are a particular case of decision trees employed to solve regression problems. They have the advantage of presenting an interpretable output, helping the end-user to get more confidence in the prediction and providing the basis for the end-user to have new insight about the data, confirming or rejecting hypotheses previously formed. Moreover, model trees present an acceptable level of predictive performance in comparison to most techniques used for solving regression problems. Since generating the optimal model tree is an NP-Complete problem, traditional model tree induction algorithms make use of a greedy top-down divide-and-conquer strategy, which may not converge to the global optimal solution. In this paper, we propose a novel algorithm based on the use of the evolutionary algorithms paradigm as an alternate heuristic to generate model trees in order to improve the convergence to globally near-optimal solutions. We call our new approach evolutionary model tree induction (E-Motion). We test its predictive performance using public UCI data sets, and we compare the results to traditional greedy regression/model trees induction algorithms, as well as to other evolutionary approaches. Results show that our method presents a good trade-off between predictive performance and model comprehensibility, which may be crucial in many machine learning applications. (C) 2010 Elsevier Inc. All rights reserved.

Network genealogy of 195-bp satellite DNA supports the superimposed hybridization hypothesis of Trypanosoma cruzi evolutionary pattern

Trypanosoma cruzi is highly diverse genetically and has been partitioned into six discrete typing units (DTUs), recently re-named T. cruzi I-VI. Although T. cruzi reproduces predominantly by binary division, accumulating evidence indicates that particular DTUs are the result of hybridization events. Two major scenarios for the origin of the hybrid lineages have been proposed. It is accepted widely that the most heterozygous TcV and TcVI DTUs are the result of genetic exchange between TcII and TcIII strains. On the other hand, the participation of a TcI parental in the current genome structure of these hybrid strains is a matter of debate. Here, sequences of the T. cruzi-specific 195-bp satellite DNA of TcI, TcII, Tat, TcV, and TcVI strains have been used for inferring network genealogies. The resulting genealogy showed a high degree of reticulation, which is consistent with more than one event of hybridization between the Tc DTUs. The data also strongly suggest that Tat is a hybrid with two distinct sets of satellite sequences, and that genetic exchange between TcI and TcII parentals occurred within the pedigree of the TcV and TcVI DTUs. Although satellite DNAs belong to the fast-evolving portion of eukaryotic genomes, in >100 satellite units of nine T. cruzi strains we found regions that display 100% identity. No DTU-specific consensus motifs were identified, inferring species-wide conservation. (C) 2010 Elsevier B.V. All rights reserved.

Developing Box-Pushing Behaviours Using Evolutionary Robotics

The context of this report and the IRIDIA laboratory are described in the preface. Evolutionary Robotics and the box-pushing task are presented in the introduction.The building of a test system supporting Evolutionary Robotics experiments is then detailed. This system is made of a robot simulator and a Genetic Algorithm. It is used to explore the possibility of evolving box-pushing behaviours. The bootstrapping problem is explained, and a novel approach for dealing with it is proposed, with results presented.Finally, ideas for extending this approach are presented in the conclusion.

Musiken ler, bilden skriker : En analys av ”anempathetic music” i film

Denna kandidatuppsats avhandlar tre stycken analyser av tre stycken filmscener från filmerna A Clockwork Orange, Reservoir Dogs och Watchmen, tre stycken exempel på scener där så kallad anempathetic music används. Denna form av musik kan beskrivas som att den distanserar sig från vad som händer i den rörliga bilden genom att förmedla den motsatta känslan, till exempel om musiken är glad och lättsam medan en våldtäkt sker i bild. Denna uppsats analyserar i dessa tre analysexempel vad sådan filmmusik kan bidra med för berättarfunktioner och meningspotential i filmexemplens narrativ. Resultaten från analysen visade på att musiken i de tre valda analysexemplen bidrar till ökad reflektion hos publiken och hur detta möjliggör för att anempathetic music kan ses som empathetic mot publiken och deras tolkning av filmscenernas narrativ.

The Music Salon in Falun During the 19th Century

The aim of the project is to examine the music salon in Falun as a part of the mining community and in the historical context of European salon culture. A specifc goal is to develop a deeper understanding about the salon when it comes to education and pedagogic ideas. Of a certain interest is Johan Henrik Munktell’s (1804-1861) education travelling (bildningsresor). Inspired by Mendelssohn’s music salon in Berlin and the early salons in Upp-sala he created his own salon in Grycksbo. A letter collection from J.H. Munktell to his father J.J. Munktell in 1828-30 can be considered a unique historical material, which places the salon in Falun in a continental context of culture, education and industrial pretensions. The results have potential to extend the knowledge of Nordic salon culture and how it has infuenced general pedagogy and music education.