the art of seo(chapter two)

***Search Engine Basics***

*Understanding How Vertical Results Fit into the SERPs*

As a direct consequence, site owners and web marketers must take into account how this incorporation of vertical search results may impact their rankings and traffic. For many of the searches shown in the previous figures, a high ranking—even in position #1 or #2 in the algorithmic/organic results—may not produce much traffic because of the presentation of the vertical results above them.

*Algorithm-Based Ranking Systems: Crawling,Indexing, and Ranking*
The search engines must execute many tasks very well to provide relevant search
results. Put simplistically, you can think of these as:
• Crawling and indexing trillions of documents (pages and files) on the Web.
• Responding to user queries by providing lists of relevant pages.

*Determining Searcher Intent and Delivering Relevant, Fresh Content*

IR scientists realized that two critical components
comprised the majority of search functionality: relevance and importance.

Document Analysis and Semantic Connectivity:
In document analysis, search engines look at whether they find the search terms in important areas of the document—the title, the metadata, the heading tags, and the body of the text.
Semantic connectivity refers to words or phrases that are commonly associated with one another. For example, if you see the word aloha,you associate it with Hawaii, not Florida.

Content Quality and User Engagement:
The other method that search engines can use to evaluate the quality of a web page is measuring actual user interaction. For example, if a large number of users who visit the web page after clicking on a search result immediately return to the search engine and click on the next result, that would be a strong indicator of poor quality.
Some interaction data include-
1.Interaction with web search results
2.Google Analytics(bounce rate,time on site,PV)
3.Google Toolbar
4.Google +1 button
5.Goo.gl

Link Analysis:
quantity,quality,relevance,nature

Evaluating Social Media Signals:
it showed a very strong correlation between +1s and ranking in Google.

Problem Words, Disambiguation, and Diversity:
For example, if someone types in a query such as cars, does he:
• Want to read reviews?
• Want to go to a car show?
• Want to buy one?
• Want to read about new car technologies?
A solution they use is to offer diverse results.
SERPs need need diversity.
Google’s testing has shown that this diversity-based approach has resulted in a higher level of satisfaction among its users.For example, the testing data for the nondiversified results may have shown lower click-through rates in the SERPs, greater numbers of query refinements, and even a high percentage of related searches performed subsequently.

Where freshness matters:
For example, when there is breaking news.QDF(query deserves freshness) applies to up-to-the-minute news coverage, but also to other scenarios such as hot, new discount deals or new product releases that get strong search volume and media coverage.

***Analyzing Ranking Factors***
Here is a high-level summary of the top nine results, in priority order:
• Domain-level link authority features
• Page-level link metrics
• Page-level keywords and content(This describes the use of the keyword term/phrase in particular parts of the HTML code on the page (<title> tag, <h1>, alt attributes, etc.).)
• Page-level keyword-agnostic features(Page-level features other than keywords)
• Domain-level brand metrics(This factor includes search volume on the website’s brand name, mentions,whether it has a presence in social media, and other brand-related metrics.)
• Usage and traffic/query data
• Page-level social metrics
• Domain-level keyword usage
• Domain-level keyword-agnostic features