From 465e17ee4aebf34696b3d38c8d986f058e967085 Mon Sep 17 00:00:00 2001 From: Martin Mares <mj@ucw.cz> Date: Mon, 9 Dec 2019 10:30:11 +0100 Subject: [PATCH] Hashing: Typos --- 06-hash/hash.tex | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/06-hash/hash.tex b/06-hash/hash.tex index 593478f..55675d6 100644 --- a/06-hash/hash.tex +++ b/06-hash/hash.tex @@ -815,7 +815,7 @@ Bloom filters are a~family of data structures for approximate representation of in a~small amount of memory. A~Bloom filter starts with an empty set. Then it supports insertion of new elements and membership queries. Sometimes, the filter gives a~\em{false positive} answer: it answers {\csc yes} even though the element is not in the set. -We will calculate the probability of false positves and decrease it at the expense of +We will calculate the probability of false positives and decrease it at the expense of making the structure slightly larger. False negatives will never occur. \subsection{A trivial example} @@ -900,7 +900,7 @@ If we set~$p$, it follows that $m \approx -n / \ln p$. Since all bands must fit of memory, we want to use $k = \lfloor M/m\rfloor \approx -M/n \cdot \ln p$ bands. False positives occur if we find~1 in all bands, which has probability $$ - (1-p)^k \approx + (1-p)^k = \e^{k\ln(1-p)} \approx \e^{-M/n \cdot \ln p \cdot \ln(1-p)}. $$ -- GitLab