Sign in
Taming Uncertainty
Sahil's Notepad
Translate This Page
Translate this page
Powered by
Microsoft® Translator
Tags
CS Fundamentals
Databases
Information Retrieval
Information Theory
Probability
Random Algs.
Browse by Tags
MSDN Blogs
>
Taming Uncertainty
>
All Tags
>
probability
Tagged Content List
Blog Post:
Random Sampling over Joins
sahilthaker
Source: On Random Sampling over Joins. Surajit Chaudhuri, Rajeev Motwani, Vivek Narasayya, Sigmod 1999. What? Random sampling as a primitive relational operator: SAMPLE(R, f) where R is the relation and f the sample fraction. SAMPLE(Q, f) is a tougher problem, where Q is a relation produced...
on
11 Feb 2008
Blog Post:
Converting Between Random Sampling Methods
sahilthaker
Sampling f fraction out of n records: Sampling with replacement Sample is a multi-set of fn records. Any record could be samples multiple times. Sampling without replacement Each successive sample is uniformly at random from the remaining records Independent Coin flips: choose a record with probability...
on
5 Feb 2008
Blog Post:
Reservoir Sampling
sahilthaker
A simple random sampling strategy to produce a sample without replacement from a stream of data - that is, in one pass: O(N) Want to sample s instances - uniformly at random without replacement - from a population size of n records, where n is not known. Figuring out n would require 2 passes. Reservoir...
on
5 Feb 2008
Page 1 of 1 (3 items)