@conference {1502308, title = {Preventing HIV Spread in Homeless Populations Using PSINET}, booktitle = {Conference on Innovative Applications of Artificial Intelligence (IAAI-15)}, year = {2015}, abstract = {Homeless youth are prone to HIV due to their engagement in high risk behavior. Many agencies conduct interventions to educate/train a select group of homeless youth about HIV prevention practices and rely on word-of-mouth spread of information through their social network. Previous work in strategic selection of intervention participants does not handle uncertainties in the social network{\textquoteright}s structure and in the evolving network state, potentially causing significant shortcomings in spread of information. Thus, we developed PSINET, a decision support system to aid the agencies in this task. PSINET includes the following key novelties: (i) it handles uncertainties in network structure and evolving network state; (ii) it addresses these uncertainties by using POMDPs in influence maximization; (iii) it provides algorithmic advances to allow high quality approximate solutions for such POMDPs. Simulations show that PSINET achieves \~{}60\% more information spread over the current state-of-the-art. PSINET was developed in collaboration with My Friend{\textquoteright}s Place (a drop-in agency serving homeless youth in Los Angeles) and is currently being reviewed by their officials.}, author = {Amulya Yadav and Marcolino, Leandro and Eric Rice and Petering, Robin and Winetrobe, Hailey and Rhoades, Harmony and Tambe, Milind and Carmichael, Heather} }