jiří materna, head of research the czech number one internet company seznam.cz
TRANSCRIPT
Jiří Materna, Head of Research
The Czech number one Internet company
Seznam.cz
www.seznam.cz
Internet portal with tens of high-quality services:• Web search (web search engine successfully competing with Google)
• Specialized search (Czech companies, e-shops)
• E-mail (the most popular free e-mail in the Czech market)
• News (covering business, politics, lifestyle, sport, whether, TV schedules, etc.)
• Entertainment (video and music online streaming)
• On-line maps (more detailed than Google maps)
• Sklik.cz (advertising system)
• And others…
What is Seznam.cz
@JiriMaterna
www.seznam.cz
• More than 1000 employees• Revenue 2.8 billion CZK (108 mil. EUR)• 2.4 million people visit Seznam.cz every day• 1.5 billion crawled web pages
-- 45 % English
-- 37 % Czech
-- 7.7 % Slovak
-- 2.3 % German
-- 8 % Others
• 500 queries per second in peak hours
Seznam.cz in numbers
@JiriMaterna
www.seznam.cz
Search engine architecture
@JiriMaterna
www.seznam.cz
• Query understanding• Graph representation:
- AND
- OR
- optional
- other relations
Query Expander
@JiriMaterna
www.seznam.cz
Search aggregators
@JiriMaterna
• Deduplication• Document sub-results• SERP restrictions• Caching
www.seznam.cz
• RC-Rank – Boosted regression oblivious trees• Hundreds of features• Our own quality measure
Ranking
@JiriMaterna
www.seznam.cz
Index & Indexer
@JiriMaterna
• Indexing: complete, daily, fresh
• Data structures:
word barrel – stores the inverted index
document barrel – stores document features
title barrel – stores processed web pages content and metadata
others – query site barrel, site barrel, link barrel, qds barrel, query url barrel, …
www.seznam.cz
• Hadoop, Giraffe, Yarn• 50 mil. documents every day• 1.5 bil. documents out of 50 bil. known
documents stored• duplicity detection
Downloader & document database
@JiriMaterna
www.seznam.cz
• Joint projects• Providing our technology• Sharing data (MetaCentrum) • …
Possible models of cooperation
@JiriMaterna
www.seznam.cz
Jiří Materna, Head of Research, [email protected]
Thank you for your attention.
@JiriMaterna