The rise and fall of (Chinese) African apparel exports

During the final years of the Multifiber Agreement (2001-2005) the US imposed quotas on Chinese apparel while it gave African apparel duty- and quota-free access. We argue that the combination of these policies led to a rapid but ephemeral rise of African exports that can be explained in part by ethnic-Chinese firms using Africa as a quota-hopping export platform. We first provide a large body of anecdotal evidence on the ethnic-Chinese apparel wave in Africa. Second, we show that Chinese exports to Africa predict US imports from the same countries and in the same apparel categories but only where transhipment incentives are present, i.e. for products facing US quotas and in countries with preferential access to the US unconstrained by rules of origin. Our estimates indicate that direct transhipment may account for around 22% of Africa's apparel exports during 2001-2008

Introduction to linear logic and ludics, part II

This paper is the second part of an introduction to linear logic and ludics, both due to Girard. It is devoted to proof nets, in the limited, yet central, framework of multiplicative linear logic and to ludics, which has been recently developped in an aim of further unveiling the fundamental interactive nature of computation and logic. We hope to offer a few computer science insights into this new theory

Realizability algebras II : new models of ZF + DC

Using the proof-program (Curry-Howard) correspondence, we give a new method to obtain models of ZF and relative consistency results in set theory. We show the relative consistency of ZF + DC + there exists a sequence of subsets of R the cardinals of which are strictly decreasing + other similar properties of R. These results seem not to have been previously obtained by forcing.Comment: 28

Profinite completions of Burnside-type quotients of surface groups

Using quantum representations of mapping class groups we prove that profinite completions of Burnside-type surface group quotients are not virtually prosolvable, in general. Further, we construct infinitely many finite simple characteristic quotients of surface groups.Comment: revised version, 17