WHAT YOU MAY NOT KNOW ABOUT SEO

For the last year I've been spending my free time after school conducting Red Bull-fueled coding sessions in the pursuit of one single goal: to bring more science to the SEO industry.

As an industry we are still only taking our first few baby steps into the world of maths, stats, and data-driven decisions. For a seemingly data-dependent industry, SEO professionals are influenced to a surprising degree by rumor, anecdotal evidence, and unscientific tests.

SEOMoz were the true visionaries in conducting correlation studies to analyze search engine algorithms. With my project, I hoped to take it that little bit further and analyze more factors on a larger dataset.

After analyzing the top 100 search results for over 10,000 keywords I had gathered 180,000,000 (one hundred and eighty million) data points on 186 potential factors in the Google algorithm. This has lead to the most comprehensive published research into Google's algorithm, and some pretty incredible findings.

With so much data and so many findings it would be impossible to go through them all here so in this post, I have hand-picked all the most important findings for readers.

Correlations are a useful but imperfect indicator of the relationship between two pieces of data, in this case search engine ranking and the factor being tested. They range from -1 to 1, a minus number meaning the factor correlates with a negative impact on ranking, and a positive number meaning ranking and the magnitude of the factor move in the same direction.

How close the correlation is to either of the 1%u2032s is an indicator of its importance/strength. A 0.7 correlation is very strong whereas a 0.05 correlation implies almost no relationship between the two variables.

For example, correlation studies have been used to link income to education. As we all know the more education we have, on average the more income we earn, but where did that statistic come from and why do most people believe it?

Correlations are used to prove relationships between two pieces of data, in this case amount of education and income, and to figure out how important that relationship is, by putting numbers behind the logic.

Here are some examples;

Participant Income   years of study

1              125,000           19

2              100,000           20

3               40,000           16

4              35,000            16

5              41000             18

6               29,000           12

7                35,000           14

8             24,000              12

9             50,000              16

10          60,000                17

In this sample, the correlation is 0.79. Just from looking at the data, you can see that the more time the study's participants spent in education, the more income they earned.

This is verified by the correlation which is a positive number (when education increases, income increases) and is very close to 1.0. This demonstrates that the relationship between education and income is a strong one.

My research findings

Now that you understand correlations, let's look at what my research revealed about SEO.

Finding 1. SEO plugins are not the answer

I'm sure you are aware there are a whole host of WordPress SEO plugins available for your blog. These plugins tend to deal primarily with on-page SEO, for example, placing keywords in the URL, title, meta description, etc.

While some plugins deal with the indexing side of SEO, which may provide some small SEO benefit, the majority tend to focus their efforts on these on-page factors.

The truth is that contrary to all the rhetoric of SEOs and industry "experts" over the last ten years, according to my research these simplistic have almost no bearing on a page's rank in Google.

That's not to say that Google hasn't developed more advanced algorithms to analyse content on a page, but certainly the traditional factors such as keywords being in title tags, h1/h2/h3 tags, etc. can be ignored when writing blog posts.

The main learning here for readers (bloggers) is that instead of worrying about search engines when you write your next blog post, you should focus 100% on the user.

Check out all these articles in common resource on how to write a great post. Guess what? None of them talk about how users love a title tag stuffed with keywords or headings tags that are meaningless space-fillers designed solely for search engine spiders.

Finding 2. You gotta love link building

The only set of factors to have all the signals tested show a significant positive correlation was links.

Without a doubt, the single most important factor in gaining search engine ranking is building links to your blog.

Page Authority, an SEOMoz metric that models the PageRank for a given URL, was by far the most influential factor in the study. What this means is that it is not only important to build links to your homepage, but also to the posts you want to get rank well in Google.

When was the last time you wrote a guest post or created a viral infographic? How much time do you spend doing keyword research or doing repetitive, mundane tasks like manually optimizing posts for keyword density?

If there is one piece of action everybody who reads this post should take, it is without a doubt to create a link-building strategy for your blog.

The proof:

link related correlations

Finding 3. Domains still matter

There's been a lot of scaremongering about exact match domains of late, but the fact is that Google still highly values EMDs that have high quality content on them.

That's the key. If you have a blog and you plan to publish great content that users will love then a EMD can be a massive help in getting you to #1 for that big keyword.

After seeing this significant positive correlation between EMDs and ranking #1 in Google, I looked a little deeper at the domain name market and learnt that there were over 200,000 domains expiring every day.

Bloggers can catch dropping domains before they go back onto the market and create incredible sites with them, which will have a natural advantage over the competition. Matt Green wrote a great post about this tactic right here on Problogger.net.

The proof:

exact match domain correlations

Research in summary

I think the key learnings from all this data for readers can be summarized into one sentence: "write for your audience not the search engines, build links to your great content, and develop your blog on a great domain with incredible domain authority."

Do you focus on SEO? What works to push your site up the search rankings? Share your thoughts on my research in the comments.