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How would you represent the following in matrix notation?

$$ 1 - \sum_{i}\sum_{j} w_i w_j p_{ij} $$

Would the following be correct?

1-(W W' p)


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Hint: put $w_j$ at the right of $p_{i,j}$ – Raymond Manzoni May 6 '13 at 22:30

I guess $w=(w_1,\ldots,w_n)^T$ is the vector and $P$ is the matrix. Then, it is rather $$1-(w^T P w)\,.$$ Expand it!

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hi i forgot to mention that it is double summation. Sorry. Would that change the answer? – user1234440 May 6 '13 at 23:44

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