@conference {17562, title = {Approximation algorithms for stochastic and risk-averse optimization}, booktitle = {Proceedings of the eighteenth annual ACM-SIAM symposium on Discrete algorithms}, series = {SODA {\textquoteright}07}, year = {2007}, month = {2007///}, pages = {1305 - 1313}, publisher = {Society for Industrial and Applied Mathematics}, organization = {Society for Industrial and Applied Mathematics}, address = {Philadelphia, PA, USA}, abstract = {We present improved approximation algorithms in stochastic optimization. We prove that the multi-stage stochastic versions of covering integer programs (such as set cover and vertex cover) admit essentially the same approximation algorithms as their standard (non-stochastic) counterparts; this improves upon work of Swamy \& Shmoys that shows an approximability which depends multiplicatively on the number of stages. We also present approximation algorithms for facility location and some of its variants in the 2-stage recourse model, improving on previous approximation guarantees.}, isbn = {978-0-898716-24-5}, url = {http://dl.acm.org/citation.cfm?id=1283383.1283523}, author = {Srinivasan, Aravind} }