August 2007
Beginner to intermediate
362 pages
10h 11m
English
Content preview from Programming Collective IntelligenceBecome an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
Chapter 4. Searching and Ranking
This chapter covers full-text search engines, which allow people to search a large set of documents for a list of words, and which rank results according to how relevant the documents are to those words. Algorithms for full-text searches are among the most important collective intelligence algorithms, and many fortunes have been made by new ideas in this field. It is widely believed that Google’s rapid rise from an academic project to the world’s most popular search engine was based largely on the PageRank algorithm, a variation that you’ll learn about in this chapter.
Information retrieval is a huge field with a long history. This chapter will only be able to cover a few key concepts, but we’ll go through the construction of a search engine that will index a set of documents and leave you with ideas on how to improve things further. Although the focus will be on algorithms for searching and ranking rather than on the infrastructure requirements for indexing large portions of the Web, the search engine you build should have no problem with collections of up to 100,000 pages. Throughout this chapter, you’ll learn all the necessary steps to crawl, index, and search a set of pages, and even rank their results in many different ways.
What’s in a Search Engine?
The first step in creating a search engine is to develop a way to collect the documents. In some cases, this will involve crawling (starting with a small set of documents and following links to others) ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.