\documentclass{beamer} \usepackage[utf8x]{inputenc} \usepackage[greek,english]{babel} \usepackage[LGR,T1]{fontenc} \usepackage{lmodern} \usepackage{amsmath} \usepackage{graphicx} \usepackage{tikz} \usetheme{Boadilla} \usecolortheme{beaver} \title[Data monetization]{Data monetization: pricing user data with the Shapley Value} \author{Thibaut \textsc{Horel}} \institute[Technicolor]{Work with {\greektext Στρατής \textsc{Ιωαννίδης}}} \setbeamercovered{transparent} \AtBeginSection[] { \begin{frame} \frametitle{Outline} \tableofcontents[currentsection] \end{frame} } \begin{document} \begin{frame} \maketitle \end{frame} \begin{frame}{Outline} \tableofcontents \end{frame} \section{Problem} \begin{frame}{Problem Overview} \end{frame} \begin{frame}{Purpose} \end{frame} \begin{frame}{Challenges} \end{frame} \section{Shapley value} \begin{frame}{Individual value} \begin{itemize} \item $S$ the set of players, a subset $S'\subset S$ is a \alert{coalition} \item $V: \mathcal{P}(S)\to \mathbf{R}$ the \alert{value} function: \begin{itemize} \item $V(S')$ is the value of the coalition $S'$ \item $V(\emptyset) = 0$ \end{itemize} \end{itemize} \alert{Question:} How to split the value of a subset across all its constituents? \alert{Goal:} design a function $\phi_i(S',V)$, the value of player $i$ in $S'$ \begin{itemize} \visible<2->{\item $\phi_i(S',V) = V(\{i\})$?} \visible<3->{``The whole is greater than the sum of its parts'' $$V(S')\neq \sum_{i\in S'} V(\{i\})$$} \visible<4->{\item $\phi_i(S',V) = V(S') - V(S'\setminus\{i\})$: the \alert{marginal contribution}?} \visible<5->{depends on the time the player joins the coalition} \end{itemize} \end{frame} \begin{frame}{Axioms} \begin{description} \item[Efficiency:] The whole value must be split $$V(S) = \sum_{i\in S} \phi_i(S,V)$$ \item[Symmetry:] Equal pay for equal contribution \alert{if} $\forall S'\subset S\setminus\{i,j\}, V(S'\cup\{i\}) = V(S'\cup\{j\})$ \alert{then} $\phi_i(S,V) = \phi_j(S,V)$ \item[Fairness:] $i$'s contribution to $j$ equals $j$'s contribution to $i$ $$\phi_i(S,V) - \phi_i(S\setminus\{j\}) = \phi_j(S,V)- \phi_j(S\setminus\{i\})$$ \end{description} \end{frame} \begin{frame}{Solution: the Shapley Value} \begin{theorem}[Shapley, 1953] \end{theorem} \end{frame} \begin{frame}{Properties} \end{frame} \section{A special case} \begin{frame}{User model} \end{frame} \begin{frame}{Recommender system} \end{frame} \begin{frame}{Value function (1)} \end{frame} \begin{frame}{Properties} \end{frame} \begin{frame}{Value function (2)} \end{frame} \begin{frame}{Conclusion and future directions} \end{frame} \end{document}