<blockquote><b>Win probability added</b> is a sport statistic which attempts to measure a player's contribution to a win by figuring the factor by which each specific play made by that player has altered the outcome of a game.<sup class="reference" id="cite_ref-1"><a href="http://en.wikipedia.org/wiki/Win_probability_added#cite_note-1"><span>[</span>1<span>]</span></a></sup> It is used for <a title="Baseball" href="http://en.wikipedia.org/wiki/Baseball">baseball</a> and <a title="American football" href="http://en.wikipedia.org/wiki/American_football">American football</a>.<sup class="reference" id="cite_ref-2"><a href="http://en.wikipedia.org/wiki/Win_probability_added#cite_note-2"><span>[</span>2<span>]</span></a></sup>

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via <a href="http://en.wikipedia.org/wiki/Win_probability_added">Win probability added - Wikipedia, the free encyclopedia</a>.