Category Archives: 技术研究

"the ranking of Google search results" 是 google 的命脉，因此很少能看到官方的说明。原因倒也无可厚非："competition and abuse"，这两件事情确实哪一个都不容忽视！

不过近日，google 负责搜索质量的 VP， Udi Manber，透露了一些有意思的资料，"Introduction to Google Search Quality"。对 search 感兴趣的千万不要错过！我列举一下我感兴趣的。

1. more than one thousand programmer/scientist years have gone directly into their development (that is to say "the ranking algorithms").
2. divided into some teams
   • The heart of the group is the team that works on core ranking
   • Another team in our group is responsible for evaluating how well we're doing
   • Another team is dedicated to new features and new user interfaces
   • There is a whole team that concentrates on fighting webspam and other types of abuse
   • There are other teams devoted to particular projects
3. PageRank [1] is still in use today, but it is now a part of a much larger system. … made significant changes to the PageRank algorithm in January, 2008.
4. some other parts
   • language models (the ability to handle phrases, synonyms, diacritics, spelling mistakes, and so on)
   • query models (it's not just the language, it's how people use it today)
   • time models (some queries are best answered with a 30-minutes old page, and some are better answered with a page that stood the test of time)
   • personalized models (not all people want the same thing).
5. Google conducts evaluations typically in three manners, (1) automated evaluations every minute, (2) periodic evaluations of our overall quality and (3) evaluations of specific algorithmic improvements.
6. In 2007, … more than 450 new improvements, about 9 per week on the average.
7. .. work on projects where the sole purpose is to simplify the algorithms. Simple is good.

Udi Manber 是我最景仰的几位科学家之一。"Chief Algorithms Officer"这个职位，就是 Amazon 专门为表彰他的贡献而首创出来的。

推荐阅读：

1. 20 (Rare) Questions for Google Search Guru Udi Manber
2. Insight Into Google's Search Quality Efforts