Probabilistic graph-coloring in bipartite and split graphs

We revisit in this paper the stochastic model for minimum graph-coloring introduced in (Murat and Paschos in Discrete Appl. Math. 154:564–586, 2006), and study the underlying combinatorial optimization problem (called probabilistic coloring) in bipartite and split graphs. We show that the obvious 2-coloring of any connected bipartite graph achieves standard-approximation ratio 2, that when vertex-probabilities are constant probabilistic coloring is polynomial and, finally, we propose a polynomial algorithm achieving standard-approximation ratio 8/7. We also handle the case of split graphs. We show that probabilistic coloring is NP-hard, even under identical vertex-probabilities, that it is approximable by a polynomial time standard-approximation schema but existence of a fully a polynomial time standard-approximation schema is impossible, even for identical vertex-probabilities, unless P=NP. We finally study differential-approximation of probabilistic coloring in both bipartite and split graphs. Part of this research has been performed while the second author was with the LAMSADE on a research position funded by the CNRS.     

Porn star/stripper/escort: economic and sexual dynamics in a sex work career

This article explores the career dynamics of performers in the gay male pornography industry, by focusing on a common career path- from porn star to stripper to escort. Between 1995 and 2005, most men performing in gay porn films, unlike contract actresses in the straight porn industry, have been unable to earn enough income to work exclusively as performers in front of the camera. The industry's constant search for new faces and fresh performers creates what sociologist Paul Cressey has called "the retrogressive dynamic": The longer a person works in a sexual occupation, the less one is paid, and the lower the status of the work venue. In the porn industry, one aspect of this process is referred to as "overexposure," during which the performer experiences a diminishing "fantasy potential" as fans lose erotic interest in the porn star who has appeared too frequently in too many movies. Performers attempt to confront the retrogressive dynamic by limiting the number of adult films in which they appear in a year, diversifying their sexual repertoire, or shifting into other roles within the industry (behind the camera, marketing, production, etc.). One common option is to pursue work in economically complementary forms of sex work such as stripping and escorting.     

Imagining the She/Male: Pornography and the Transsexualization of the Heterosexual Male

This essay explores the emergence of a form of sexual desire that did not strictly exist before the late 20th century—desire for the “pre-op” male-to-female (MTF) transsexual woman—a partially feminized male-bodied person who typically has breasts developed through hormone therapy or breast augmentation and some other female characteristics but who has not yet undergone female-to-male sex-reassignment surgery. The historical development of this new form of sexual desire is documented, in part, by the emergence of the transsexual pornographic video as a heterosexual male genre. The primary focus of this article is on the male spectator, with a secondary emphasis on the “male” performer. It explores how both male performers and consumers self-identify, what concepts of gender that both performers and consumers hold, and how the adult entertainment industry organizes and reflects sex and gender conventions and practices.