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| author | Stratis Ioannidis <stratis@stratis-Latitude-E6320.(none)> | 2013-07-06 20:32:20 -0700 |
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| committer | Stratis Ioannidis <stratis@stratis-Latitude-E6320.(none)> | 2013-07-06 20:32:20 -0700 |
| commit | 6f255bcbe303748bfface378be199cb9d9b5012f (patch) | |
| tree | 8e72cad4a3c6922305a025644326d7b4c7a2078b | |
| parent | 081cddcb61cc25216994c6328aa2d9cebfcc33cd (diff) | |
| download | recommendation-6f255bcbe303748bfface378be199cb9d9b5012f.tar.gz | |
sherman morisson
| -rw-r--r-- | appendix.tex | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/appendix.tex b/appendix.tex index 3c2fed8..5dce278 100644 --- a/appendix.tex +++ b/appendix.tex @@ -178,7 +178,7 @@ the proof of the lemma. \qed \subsection{Proof of Lemma~\ref{lemma:rounding}}\label{proofoflemmarounding} %\begin{proof} We give a rounding procedure which, given a feasible $\lambda$ with at least - two fractional components, returns some feasible $\lambda'$ with one less fractional + two fractional components, returns some feasible $\lambda'$ with one fewer fractional component such that $F(\lambda) \leq F(\lambda')$. Applying this procedure recursively yields the lemma's result. @@ -284,7 +284,7 @@ contains the strictly feasible point $\lambda=(\frac{1}{n},\ldots,\frac{1}{n})$. is the right-hand side of the lemma. For the left-hand side, note that $\tilde{A}(\lambda) \preceq A_n$. Hence $\partial_iL(\lambda)\geq \T{x_i}A_n^{-1}x_i$. - Using the Sherman-Morrison formula, for all $k\geq 1$: + Using the Sherman-Morrison formula \cite{sm}, for all $k\geq 1$: \begin{displaymath} \T{x_i}A_k^{-1} x_i = \T{x_i}A_{k-1}^{-1}x_i - \frac{(\T{x_i}A_{k-1}^{-1}x_k)^2}{1+\T{x_k}A_{k-1}^{-1}x_k} @@ -325,7 +325,7 @@ Similarly, we define $\mathcal{L}_{c}\defeq\mathcal{L}_{c, 0}$ the lagrangian of Let $\lambda^*$ be primal optimal for \eqref{eq:perturbed-primal}, and $(\mu^*, \nu^*, \xi^*)$ be dual optimal for the same problem. In addition to primal and -dual feasibility, the KKT conditions give $\forall i\in\{1, \ldots, n\}$: +dual feasibility, the Karush-Kuhn-Tucker (KKT) conditions \cite{boyd2004convex} give $\forall i\in\{1, \ldots, n\}$: \begin{gather*} \partial_i L(\lambda^*) + \mu_i^* - \nu_i^* - \xi^* c_i = 0\\ \mu_i^*(\lambda_i^* - \alpha) = 0\\ @@ -616,7 +616,7 @@ OPT \leq \frac{e}{e-1}\big( 3 V(S_G) + 2 V(i^*)\big). \end{displaymath} \end{lemma} -Using Proposition~\ref{prop:relaxation} and~\ref{lemma:greedy-bound} we can complete the proof of +Using Proposition~\ref{prop:relaxation} and Lemma~\ref{lemma:greedy-bound} we can complete the proof of Theorem~\ref{thm:main} by showing that, for any $\varepsilon > 0$, if $OPT_{-i}'$, the optimal value of $L$ when $i^*$ is excluded from $\mathcal{N}$, has been computed to a precision $\varepsilon$, then the set @@ -660,7 +660,7 @@ Thus, if $C$ is such that $C(e-1) -6e +2 > 0$, \end{align*} Finally, using Lemma~\ref{lemma:greedy-bound} again, we get \begin{equation}\label{eq:bound2} - OPT(V, \mathcal{N}, B) \leq + OPT \leq \frac{3e}{e-1}\left( 1 + \frac{4e}{C (e-1) -6e +2}\right) V(S_G) + \frac{2e\varepsilon}{C(e-1)- 6e + 2}. \end{equation} |
