PageRank

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Mathematical PageRanks for a simple network, expressed as percentages. (Google uses a logarithmic scale.) Page C has a higher PageRank than Page E, even though there are fewer links to C; the one link to C comes from an important page and hence is of high value. If web surfers who start on a random page have an 85% likelihood of choosing a random link from the page they are currently visiting, and a 15% likelihood of jumping to a page chosen at random from the entire web, they will reach Page E 8.1% of the time. (The 15% likelihood of jumping to an arbitrary page corresponds to a damping factor of 85%.) Without damping, all web surfers would eventually end up on Pages A, B, or C, and all other pages would have PageRank zero. In the presence of damping, Page A effectively links to all pages in the web, even though it has no outgoing links of its own.

PageRank is a link analysis algorithm, named after Larry Page^[1] and used by the Google Internet search engine, that assigns a numerical weighting to each element of a hyperlinked set of documents, such as the World Wide Web, with the purpose of "measuring" its relative importance within the set. The algorithm may be applied to any collection of entities with reciprocal quotations and references. The numerical weight that it assigns to any given element E is referred to as the PageRank of E and denoted by
The name "PageRank" is a trademark of Google, and the PageRank process has been patented (U.S. Patent 6,285,999). However, the patent is assigned to Stanford University and not to Google. Google has exclusive license rights on the patent from Stanford University. The university received 1.8 million shares of Google in exchange for use of the patent; the shares were sold in 2005 for $336 million.^[2][3]

Contents 1 Description 2 History 3 Algorithm 3.1 Simplified algorithm 3.2 Damping factor 3.3 Computation 3.3.1 Iterative 3.3.2 Algebraic 3.3.3 Power Method 3.3.4 Efficiency 4 Variations 4.1 PageRank of an undirected graph 4.2 Google Toolbar 4.3 SERP Rank 4.4 Google directory PageRank 4.5 False or spoofed PageRank 4.6 Manipulating PageRank 4.7 The intentional surfer model 4.8 Other uses 5 nofollow 6 Deprecation 7 See also 8 Notes 9 References 10 Relevant patents 11 External links

Description

Cartoon illustrating basic principle of PageRank

A PageRank results from a mathematical algorithm based on the webgraph, created by all World Wide Web pages as nodes and hyperlinks as edges, taking into consideration authority hubs such as cnn.com or usa.gov. The rank value indicates an importance of a particular page. A hyperlink to a page counts as a vote of support. The PageRank of a page is defined recursively and depends on the number and PageRank metric of all pages that link to it ("incoming links"). A page that is linked to by many pages with high PageRank receives a high rank itself. If there are no links to a web page there is no support for that page.
Numerous academic papers concerning PageRank have been published since Page and Brin's original paper.^[4] In practice, the PageRank concept has proven to be vulnerable to manipulation, and extensive research has been devoted to identifying falsely inflated PageRank and ways to ignore links from documents with falsely inflated PageRank.
Other link-based ranking algorithms for Web pages include the HITS algorithm invented by Jon Kleinberg (used by Teoma and now Ask.com), the IBM CLEVER project, and the TrustRank algorithm.

History

PageRank was developed at Stanford University by Larry Page (hence the name Page-Rank^[5]) and Sergey Brin as part of a research project about a new kind of search engine.^[6] Sergey Brin had the idea that information on the web could be ordered in a hierarchy by "link popularity": a page is ranked higher as there are more links to it.^[7] It was co-authored by Rajeev Motwani and Terry Winograd. The first paper about the project, describing PageRank and the initial prototype of the Google search engine, was published in 1998:^[4] shortly after, Page and Brin founded Google Inc., the company behind the Google search engine. While just one of many factors that determine the ranking of Google search results, PageRank continues to provide the basis for all of Google's web search tools.^[8]
PageRank has been influenced by citation analysis, early developed by Eugene Garfield in the 1950s at the University of Pennsylvania, and by Hyper Search, developed by Massimo Marchiori at the University of Padua. In the same year PageRank was introduced (1998), Jon Kleinberg published his important work on HITS. Google's founders cite Garfield, Marchiori, and Kleinberg in their original paper.^[4]
A small search engine called "RankDex" from IDD Information Services designed by Robin Li was, since 1996, already exploring a similar strategy for site-scoring and page ranking.^[9] The technology in RankDex would be patented by 1999^[10] and used later when Li founded Baidu in China.^[11][12] Li's work would be referenced by some of Larry Page's U.S. patents for his Google search methods.^[13]

Keyword Research Tool Review: Google AdWords

Keywords are important. I’ve heard from several potential clients recently who have talked to other “professionals” who told them keywords are no longer important for SEO, and that good content is all you really need.
Here’s the thing. Keywords are language. They’ll always be important because words are how we communicate with each other.
So until someone invents the microchip that can be implanted in your brain and read your thoughts without using words, you’ll need to think about language in marketing. And I can only hope that those potential clients were told this by one seriously misguided vendor.
With the ubiquitous need for keywords, there are a lot of tools out there that claim to do keyword research better. So I present to you, a series on Free Keyword Tools!
Let’s start with the Google Keyword Tool. This is what we all use, and like it or not, it’s the best free tool available. It’s tied directly into Adwords, and it uses search frequency from Google (although that’s debatable, see below). If you don’t sign in with an Adwords account, you’ll have to enter the captcha every time you want to do a search.
Lately, I’ve been seeing the captcha show up even when I’m logged in though, so you may not be completely free of this annoyance. By the way, it’s free to set up an Adwords account, and you don’t have to have anything live in it to be able to use the keyword tool.

Cool Features Of The Google Keyword Tool

• The ability to switch from broad to exact or phrase match volumes. This can really help identify which keywords you want to set on which match types, and for SEO, it can help to hint at which keyword phrase has the overall highest volume in a niche.
• The tool has lots of options for information about the keywords, which is somewhat hidden in the “columns” drop down menu – shown below. These are primarily designed for paid search, but they have some value in regular research as well.

Column options in the Google Keyword Tool

• Global vs. Local Monthly search volumes. The difference here is that one shows you only the local area you set up (defaulted to United States) and the other shows you volume for the entire world.
• Be cautious using Global when you really mean Local, otherwise you’ll get keywords like “handy” instead of “mobile phone” showing as they have a lot of volume, even though only Germans call it a “handy”. Adjust your local settings here:

Options in the Google Keyword Tool

• Approximate CPC and Competition are both useful for seeing what the competition is like for these keywords in the paid arena. It logically follows that those keywords would also be competitive organically or in any other context, and it can be a good way (along with volume) to make relative decisions.
• Local Search Trends is also pretty cool, as it takes data from Google Insights and displays it directly in the keyword tool. The bars that are shown represent the previous 12 months’ search trend. Here’s an example for “summer olympics 2012″ which clearly shows that interest in this topic has been increasing, just as we would expect.

Trends for "summer olympics 2012"

• Search Share and Extracted from Webpage seem like they’d be an SEO’s dream, but I’ve been unable to get this feature to work properly, even with an active Adwords account. In theory, these two data points would show you (respectively) when your site showed up in organic search for a given keyword and what webpages on your site already match this keyword. We can continue to dream, but I think it’s likely this feature will only work when you have an active Adwords account live – so you can decide whether or not to bid on a keyword in paid.
• The ad group ideas (beta) is really pretty cool. While I would never advocate using it to set up your ad groups, it can be very useful for categorizing keywords into niches. The fact that it saves your “ideas” and that you can check all keywords in a “group” at the same time makes me have to use those complicated excel formulas a bit less often.
• Include/Exclude terms allows you to really narrow things down. An example from real life – I was searching for “estate planning” terms, and didn’t want anything associated with real estate. By adding the word “real” into the exclude terms box, I got a nicely filtered list of just what I needed.
• The category drop down can also be useful, particularly when you’re doing work for a niche within a larger context. For example, I was doing some work for an attorney who helps with adoptions. By narrowing the category to “Law and Government”, I was able to take out all those keywords like “teenage pregnancy adoption” that aren’t relevant enough to the attorney trying to sell services.
• The “only show ideas closely related to my search terms” box is unchecked by default, but you may want to check it if you are working with some really general search terms. Basically, what this box does is require that the keywords the tool returns have at least one of your keywords in it. If you leave this box unchecked, you may get keywords like “car quote” when you search “car insurance”. If you leave the box checked, you won’t get keywords like “insure car”, so think carefully about whether you want to check this or not.
• Finally, the “Locations and Languages” feature under “Advanced Options and Filters” is a must for anyone doing international research. Maybe someday they’ll allow us to filter by region or state of the US too. That would be helpful.

What Is Social Media Marketing

Social media marketing refers to the process of gaining traffic or attention through social media sites.
Social media itself is a catch-all term for sites that may provide radically different social actions. For instance, Twitter is a social site designed to let people share short messages or “updates” with others. Facebook, in contrast is a full-blown social networking site that allows for sharing updates, photos, joining events and a variety of other activities.
Why would a search marketer — or a site about search engines — care about social media? The two are very closely related.
Social media often feeds into the discovery of new content such as news stories, and “discovery” is a search activity. Social media can also help build links that in turn support into SEO efforts. Many people also perform searches at social media sites to find social media content. The articles from Search Engine Land below give some more background on all of this:

• Beyond Google: Social Media Engines First, Other Search Engines Second
• How Search-Like Are Social Media Sites?

Advice At Search Engine Land
Here at Search Engine Land, we provide paid search advertising information and news in a variety of ways:
How To: Social Media Marketing is our section that is devoted to practical tips and tactics about social media marketing. Also see the related How To: Twitter section.
Let’s Get Social is Search Engine Land’s column that covers different social media marketing topics every week.
Social Media Marketing Library Archives: This area of Search Engine Land provides a collection of all stories we’ve written on the topic of social media. Also check out the related categories of linkbait and URL shorteners.
In addition to covering social media marketing generally, Search Engine Land also has areas specifically about particular major social media sites and social search sites:

• Delicious
• Digg
• Facebook
• Foursquare
• Google Buzz
• Google Social Search (and see our What Is Google Social Search guide)
• Gowalla
• Twitter
• YouTube
• Social Search Engines
• Word Of Mouth & Buzz Search Engines

Link Building & Ranking In Search Engines

Links were the first major “Off The Page” ranking factor used by search engines. No, Google wasn’t the first search engine to count links as “votes,” but it was the first search engine to massively depend on link analysis as a way to improve relevancy.
Today, links remain the most important external signal that can help a web site rise in the rankings. But some links are more equal than others….

Lq: Link Quality

If you were sick, which would you trust more? The advice of five doctors or fifty people you didn’t know but who offered their opinions as you walked down the street.
Unless you’ve had a really bad experience with doctors, you’re probably going to trust the doctor advice more. Even though you’re getting fewer opinions, you’re getting those opinions from experts. They’re quality opinions.
In the same way, search engines do count all the links pointing at web sites (except those blocked using nofollow or other methods). But they don’t count them all equally. They give more weight to the links that are considered to be of better quality.
What’s a quality link? It’s one of those “you’ll know it when you see it” types of things, in many cases. But a link from any large, respectable site is going to be higher on the quality scale than a link you might get from commenting on a blog.
To learn more about link quality and how Google in particular examines links, see this tutorial from us:

• What Is Google PageRank? A Guide For Searchers & Webmasters

These articles from us provide some additional tips on getting quality links:

• Getting Links From Known, Quality Linkers
• My Quality Link May Not Be Your Quality Link
• A Link Building Blueprint: The Foundation

Also be sure to check out our Link Week column, which provides information about link building every week.

Lt: Link Text / Anchor Text

Amazon has millions of links pointing at it. Yet, it doesn’t rank for “cars.” It does rank for “books.” Why? Many of those links pointing at Amazon say the word “books” within the links. Relatively few will say “cars,” since Amazon doesn’t sell cars.
The words within a link — the link text or “anchor text” — are seen by search engines as a way that one web site is describing another. It’s as if someone’s pointing at you in real life and saying “books,” declaring you to be an expert on that topic.
Often, you can’t control the words people use to link to you. But if you have the opportunity to influence this, you should seek to. It’s a powerful ranking factor.
To learn more about anchor text, see our tutorial below:

• Google Now Reporting Anchor Text Phrases

Ln: Number Of Links

While you want link quality over sheer number of links, plenty of sites have found that getting many links can add up.
In particular, viral linkbaiting campaigns can be effective and something even search engine representatives have suggested.
But in your quest for links, don’t fire up automated software and begin blog spamming. That’s a bad thing, in many ways, as we’ll explore later in this guide.

What Is SEO / Search Engine Optimization?

SEO stands for “search engine optimization.” It is the process of getting traffic from the “free,” “organic,” “editorial” or “natural” listings on search engines. All major search engines such as Google, Yahoo and Bing have such results, where web pages and other content such as videos or local listings are shown and ranked based on what the search engine considers most relevant to users. Payment isn’t involved, as it is with paid search ads.

Google Lied about Manually Changes

The Lie was told here by Udi Manber, and repeated by Matt Cutts. And I quote:

‘At Google we do not manually change results. For example, if we find for a particular query that result No. 4 should be result No. 1, we do not have the capability to manually change it. We made that decision not to put that capability in the algorithm—we have to go and actually change the algorithm.”

Contrast that with the story from 2 days ago from the official Google Blog:

“We created about 100 “synthetic queries”—queries that you would never expect a user to type, such as [hiybbprqag]. As a one-time experiment, for each synthetic query we inserted as Google’s top result a unique (real) webpage which had nothing to do with the query. Below is an example:”

There is no way to reconcile those two statements. If Google sees someone at number 4 that they want at number 1, they can remove the number 4 result with their manual spam filter, and then manually insert it to number 1.

This is not nitpicking: they have the capability and they have used it. They have used it more than for legality or for spam, they used it at the very least for their recent PR stunt.

This is on par with “Read My Lips, No new Taxes”

They lied. They were caught.

Do not trust Matt Cutts.

Do not trust Udi Manber.

DO NOT TRUST GOOGLE.

They are bold face liars.

They can and do manually change their search results. They can and do manually put whoever they want at number one: regardless of what they have said in the past.

Matt Cutts Talks Google Penguin, Negative SEO, Disavowing Links, Bounce Rate & More

What is Google looking for in a high quality website, worthy of top rankings? Well according to Matt Cutts, head of Google’s web spam team, you must first use as many keywords as possible; the optimal keyword density is actually 77 percent. Definitely link to porn sites. Annoying users: that’s a plus. You do get a boost for running AdSense, he revealed. Oh, and all those other search engines - Bing, Blekko, DuckDuckGo - they’re a bunch of hackers doing illegal things. You heard it hear, folks.

If you bought any of that, I have some icebergs I’d like to sell you. That video was actually a mash-up spoof Google put out, one that was played at the beginning of You & A with Matt Cutts at SMX Advanced 2012.

All jokes aside, Cutts got into some great topics and dispelled some modern-day SEO myths in his session. Here are the highlights.

Is Penguin a Penalty?

No, neither Penguin nor Panda are manual penalties, Cutts said. He explained that Penguin was designed to tackle “the stuff in the middle;” between fantastic, high quality content and spam. Panda was all about spam, but the need for Penguin arose from this middle ground.

“It does demote web results, but it’s an algorithmic change, not a penalty. It’s yet another signal among over 200 signals we look at,” he said.

A penalty is a manual action taken against a site and you will “pretty much always” be notified in Webmaster Tools if it’s a penalty affecting your site.

Will a Reconsideration Request Help You Recover From Penguin?

No. “People who think it should rank higher after Penguin can let us know and we can look at it, and in a couple of instances, it actually helped us make a couple of tweaks to the algorithm.” You should submit a reconsideration request if you receive a warning.
Negative SEO - Will Google Add an Option to Disavow Links?

They sure seem to be thinking about it. People have been asking about negative SEOfor a long time, Cutts said. He noted that Google has changed their documentation over time to reflect that negative SEO is not impossible, but it is difficult. Google is “talking about” being able to enable disavowing links, possibly within a few months.
Did Google Send WMT Notifications About Penguin?

Google is trying to be more transparent by sending out more warnings, he said. Only a single-digit percent of those 700,000 unnatural link warnings that went out around the time of Penguin were actually Penguin-related. The majority were for obvious black-hat tactics.

Is Google Trying to Make a Point About Buying Links?

Yes, they are. According to Cutts, “People don’t realize, when you buy links, you might think you’re very careful, that you have no footprints, but you may be getting into business with someone who’s not as careful. People need to realize as we build new tools, it becomes a higher-risk endeavor.”

Is SEO Going to Get More Difficult?

Yes. He notes that it’s become more challenging over the past five to seven years and SEOs should expect that trend to continue and even increase.

Does That Mean Google Hates SEOs?

Of course not. Though Cutts did hand out a spanking for SEOs who buy or sell links: “There are people who continue to sell links, although they don’t do any good, and that’s part of how SEO has a bad reputation.”

Later, he said he would consider giving link building for non-profits a try to better understand what SEOs are facing. When asked about the war on SEOs, he said, “There’s no war on SEOs!” and that it’s just a war on spam.

Google, Yahoo, MSN Unite On Support For Nofollow Attribute For Links

In the first cooperative move for nearly ten years, the major search engines have unveiled a new indexing command for web authors that they all recognize, one that they hope will help reduce the link and comment spam that plagues many web sites, especially those run by bloggers.

The new "nofollow" attribute that can be associated with links was originated as an idea by Google several weeks ago and pitched past MSN and Yahoo, as well as major blogging vendors, gaining support.