Erratum: Agbio groups join BIO

Erratum

Automorphisms of free groups. I — erratum

I report an error in Theorem A of Automorphisms of free groups. I , New York J. Math. 19 (2013), 395–421, where it was claimed that two filtrations of the group of IA automorphisms of a free group coincide up to torsion. In fact, using a recent result by Day and Putman, I show that, for a free group of rank 3, the opposite conclusion holds, namely that the two series differ rationally.

Join the Club: Enabling Self-Organizing Groups on the Net

The goal of this project is to establish how social agents can help humans form groups and achieve beneficial outcomes in their task-oriented use of cyberspace. To achieve this goal, the social challenges faced by humans trying to form groups, and the design problems of creating agents that can operate effectively in a mixed human-agent context, must both be addressed. The approach in the propo...

Why join groups? Lessons from parasite-manipulated Artemia.

Grouping behaviours (e.g. schooling, shoaling and swarming) are commonly explicated through adaptive hypotheses such as protection against predation, access to mates or improved foraging. However, the hypothesis that aggregation can result from manipulation by parasites to increase their transmission has never been demonstrated. We investigated this hypothesis using natural populations of two c...

Erratum to “Fundamental Groups of Some Special Quadric Arrangements”

This erratum relates to our work “Fundamental groups of some special quadric arrangements”. The original Theorems 2.2, 2.5, 2.8 and Propositions 2.3(ii)(iii), 2.6(ii)(iii), 2.9(ii)(iii) have wrong results. They need to be rephrased. Corollaries 2.4 and 2.7 are incomplete, and they are extended. We add a new Corollary 2.10, which does not appear in the original paper. Proposition 3.1 has a wrong...