lec14a - Click to edit Master subtitle style 2/7/11 Sundar...

Info iconThis preview shows pages 1–5. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Click to edit Master subtitle style 2/7/11 Sundar B. CS C341 / I S C361 Data Structures & Algorithms Dictionary Data Structures - Hashing Bloom Filters- Motivation- Implementation- Analysis- General Scenario- Applications. Las Vegas vs. Monte Carlo Techniques 11 2/7/11 Sundar B. 2/7/11 Sundar B. Bloom Filters - Motivation Consider this outline for stemming : for each word w if (w is an exception word) then getStem(w,D) else apply-simple-rule(w) Cost for checking exceptions: N * Td where N is # words and Td is lookup time (on disk) 2/7/11 22 Sundar B. Need dictionary lookup on disk 2/7/11 Sundar B. Bloom Filters - Motivation Suppose we can trade-off space for false positives (in lookup): for each word w if (w is in Dm ) // in-memory lookup (probabilistic) then { s = getStem(w, Dd) // disk lookup (deterministic) if invalid(s) then apply-simple-rule(w); } else { apply-simple-rule(w); } Cost for checking exceptions: N * Tm + (r + f )*N*Td 2/7/11 33 Sundar B. 2/7/11 Sundar B....
View Full Document

Page1 / 10

lec14a - Click to edit Master subtitle style 2/7/11 Sundar...

This preview shows document pages 1 - 5. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online