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1,171 bytes removed ,  20:14, 25 April 2013
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and is also interested in energy and other domains where her work may
 
and is also interested in energy and other domains where her work may
 
apply.
 
apply.
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The first part of this talk focuses on a network diffusion model
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  that was recently introduced by Goldberg & Liu (SODA'13). Goldberg &
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  Liu's model adapts the earlier linear threshold model of Kempe,
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  Kleinberg & Tardos (KDD'03) in an effort to capture aspects of
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  technology adaptation processes in networks. We present new,
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  improved, yet simple algorithms for the so called Influence
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  Maximization problem in this setting.
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  A key component of our algorithm is a Langrangean multiplier
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  preserving (LMP) algorithm for the Prize-collecting Node-weighted
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  Steiner Tree problem (PC-NWST). This problem had been studied in
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  prior work by Moss and Rabani (STOC'01 & SICOMP'07) who presented a
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  primal-dual O(log |V|) approximate and LMP algorithm, and showed
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  that this is best possible unless NP=P.
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  We demonstrate that Moss & Rabani's algorithm for PC-NWST is
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  seriously flawed. We then present a new, fundamentally different
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  primal-dual method achieving the same performance guarantee. Our
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  algorithm introduces several novel features to the primal-dual
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  method that may be of independent interest.
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  Joint work with Laura Sanita and Sina Sadeghian