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sdmia_invited_speakers [2015/09/26 08:28] matthijs |
sdmia_invited_speakers [2015/10/18 09:32] matthijs |
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[[http://teamcore.usc.edu/tambe/|USC]] | [[http://teamcore.usc.edu/tambe/|USC]] | ||
- | Title: TBD\\ | + | Joint work with Eric Rice, Amulya Yadav, and Robin Petering. |
+ | |||
+ | Title: **PSINET: Assisting HIV Prevention Amongst Homeless Youth using POMDPs**\\ | ||
Abstract:\\ | Abstract:\\ | ||
- | TBD | + | Homeless youth are prone to Human Immunodeficiency |
+ | Virus (HIV) due to their engagement in high risk behavior | ||
+ | such as unprotected sex, sex under influence of | ||
+ | drugs, etc. Many non-profit agencies conduct interventions | ||
+ | to educate and train a select group of homeless | ||
+ | youth about HIV prevention and treatment 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’s structure and 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; | ||
+ | and (iii) it provides algorithmic advances to allow high | ||
+ | quality approximate solutions for such POMDPs. We are about | ||
+ | to conduct a pilot test study with homeless youth in Los Angeles; | ||
+ | we will present a progress report. | ||
=== Jason Williams === | === Jason Williams === | ||
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[[http://rbr.cs.umass.edu/shlomo/|UMass Amherst]] | [[http://rbr.cs.umass.edu/shlomo/|UMass Amherst]] | ||
- | Title: TBD\\ | + | Title: **Do We Expect Too Much from DEC-POMDP Algorithms?**\\ |
Abstract:\\ | Abstract:\\ | ||
- | TBD | + | Sequential decision models such as DEC-POMDPs are powerful and elegant approaches for planning in situations that involve multiple cooperating decision makers. They are powerful in the sense that we can, in principle, capture a rich class of problems. They are elegant in the sense that they include the minimal set of ingredients needed to analyze these problems and facilitate rigorous mathematical examination of their fundamental properties. An optimal solution of a DEC-POMDP explicitly answers the question of what should an agent do to maximize value. Implicitly, an optimal solution answers many other questions including the appropriate assignment of meaning to internal memory states, appropriate adoption of goals and subgoals, appropriate assignment of roles to agents, and appropriate assignment of meaning to messages that agents exchange. In fact, an optimal policy optimizes all these choices implicitly. In this talk, I argue that this is just too much to expect from a computational point of view. There is much to be gained by decomposing the planning problem in a way that some of these questions are answered first and a simplified planning problem is then solved. I discuss a few examples of such decompositions and examine their contribution to the scalability of planning algorithms |