diff --git a/approx_alg.tex b/approx_alg.tex index 3183db9..0024ce7 100644 --- a/approx_alg.tex +++ b/approx_alg.tex @@ -192,8 +192,12 @@ The algorithm to prove~\Cref{lem:approx-alg} follows from the following observat Given the above, the algorithm is a sampling based algorithm for the above sum: we sample $(v,c)\in \expandtree{\etree}$ with probability proportional\footnote{We could have also uniformly sampled from $\expandtree{\etree}$ but this gives better parameters.} %\AH{Regarding the footnote, is there really a difference? I \emph{suppose} technically, but in this case they are \emph{effectively} the same. Just wondering.} %\AR{Yes, there is! If we used uniform distribution then in our bounds we will have a parameter that depends on the largest $\abs{coef}$, which e.g. could be dependent on $n$. But with the weighted probability distribution, we avoid paying this price. Though I guess perhaps we can say for the kinds of queries we consider thhese coefficients are all constants?} -to $\abs{c}$ and compute $Y=\indicator{\monom\mod{\mathcal{B}}\not\equiv 0}\cdot \prod_{X_i\in \var\inparen{v}} p_i$. Taking enough samples and computing the average of $Y$ gives us our final estimate. Algorithm~\ref{alg:mon-sam} has the details. -\OK{Even if the proof is offloaded to the appendix, it would be useful to state the formula for $N$ (line 4 of \Cref{alg:mon-sam}), along with a pointer to the appendix.} +to $\abs{c}$ and compute $Y=\indicator{\monom\mod{\mathcal{B}}\not\equiv 0}\cdot \prod_{X_i\in \var\inparen{v}} p_i$. Taking $\numsamp$ samples and computing the average of $Y$ gives us our final estimate. Algorithm~\ref{alg:mon-sam} has the details for $\approxq$. The derivation of $\numsamp$ (\Cref{alg:mon-sam-global2}) can be found in~\Cref{app:subsec-th-mon-samp}, and from those results, one can further see that +\begin{equation*} +2\exp{\left(-\frac{\samplesize\error^2}{2}\right)}\leq \conf \implies\samplesize \geq \frac{2\log{\frac{2}{\conf}}}{\error^2}. +%\exp{\left(-\frac{\samplesize\error^2}{2}\right)}\leq \frac{\conf}{2}\\ +%\frac{\samplesize\error^2}{2}\geq \log{\frac{2}{\conf}}\\ +\end{equation*} %We state the approximation algorithm in terms of a $\bi$. %\subsubsection{Description} diff --git a/hardness-app.tex b/hardness-app.tex index dad9010..8ce5b66 100644 --- a/hardness-app.tex +++ b/hardness-app.tex @@ -379,7 +379,7 @@ The claim on the runtime follows since which completes the proof. We now return to the proof of~\Cref{lem:mon-samp}: -\subsection{Proof of Theorem \ref{lem:mon-samp}} +\subsection{Proof of Theorem \ref{lem:mon-samp}}\label{app:subsec-th-mon-samp} Consider now the random variables $\randvar_1,\dots,\randvar_\numvar$, where each $\randvar_i$ is the value of $\vari{Y}_{\vari{i}}$ after~\Cref{alg:mon-sam-product} is executed. In particular, note that we have \[Y_i= \onesymbol\inparen{\monom\mod{\mathcal{B}}\not\equiv 0}\cdot \prod_{X_i\in \var\inparen{v}} p_i,\] where the indicator variable handles the check in~\Cref{alg:check-duplicate-block}