I was recently inspired by a post by MikeTek, Examining the Top 150 In-Linked Posts at SEOmoz.  While the information was very informative, it was taken from a limited sample of the over 3,800 post on SEOmoz.  Along with the small sample size, the data was not proportional to other categories and posts.  Mike encouraged anyone with a little automation skills to look into all the data on SEOmoz and really look into what makes a post link worthy. 

For this post we will be looking only at In Linking Domains (ILDs) which is a great way to determine if a post is popular throughout the net.  For example if you have a site like dummy-domain.com that links to your post 1,000 times throughout its site, it would count as 1 ILD.  A great viral post will have a large number of ILDs along with a large number of links.

LET'S START WITH THE DATA

Much like Mike’s data, there were some categories that collected more links than others.  In fact there were five categories that have the most domains linking to them, Link Building (1,448 domains), Google (1,419 domains), Technical Issues (1,243 domains), Miscellaneous (1,215 domains), and Whiteboard Friday (1,044 domains).  See the graph below for the top 30 of the SEOmoz categories.

The data in the chart above can be a little misleading because some of those categories have many more posts than others do.  To make all the data proportional, I took the total number of linking domains and divided it by the number of posts.  The chart changes considerably when the data becomes normalized.  From the chart below you can see that the top 3 categories are Webdev (19), Technical Issues (14), and On-Page Issues (10).

From the charts above it’s easy to say that “Link Building” is a very popular blog topic but it doesn’t always draw in the links like other topic can.  Part of that could be because of the difference in options on link building techniques.  Topics like “Technical Issues” and “On-Page Issues” the types of content that most people will agree on and possibly want to share with others in the business.

To take the study a little further, I stored all the post’s title’s and created a title word cloud for the top 10% of the 3,800.  This hopefully will give you an idea of what topics could have the possibility of being link worthy in your future post.  I was going to try and come up with a “Super” title based on the words in the cloud but couldn’t come up with anything catchy.  Maybe one of you Mozzers can come up with something amazing from the cloud.

Like Mike did in his previous post, let’s take a look at the content in the posts: images, list, and videos.  In the chart below you will see that having a just a list in a post compared to just text, doubles the average number of linking domains.  Have a video compared to just text will almost triple the average number of linking domains.  A post that has an image and a list will also triple the average number of linking domains to the post.

I’m sure many of you are like me and do a quick scan of the post before actually reading it.  By adding images, videos, and lists, it makes it easy to get a quick synopsis on what the post is about, encouraging people to go back and do a full read along with a possible link.  Adding Images and Lists are easy to do and could result in a post that is more link worthy.

I also recorded the length of the post to see if it had an effect on the average number of linking domains.  The length recorded was only that of the post and not the comments or other areas of the page to keep the data accurate.  I’ve read that most blog post should be kept to 500 words or less.  That information seems to be incorrect if you are going to post on SEOmoz and want it to be link worthy.  The chart below shows that posts with 1800 or more words have a much higher average of linking domains.

BIGGEST TAKEAWAYS

I feel the real take away from this post is in the last two graphics summarized below:

• Content is most important thing to a posts but posts with extra visual content attract extra links.
• By adding simple visual content, like lists and images, can increase the number of ILDs by good percent.
• Posts with videos included will attract almost 3 times more ILDs than a plain text post.
• Posts with all three media types (videos, images, and lists) will attract almost 6 times more ILDs than a plain text post.
• Contrary to common beliefs, large posts seem to attract more links than posts with 900 words or less.
• Posts with between 1800 and 3000 words will attract more than 15 times more ILDs than a post with less than 600 words.

The first part of this study was only with SEOmoz data and in the next part of this study I have decided to take on a huge project and taking a look at some of the top SEO/Internet Marketing blogs on the web.  With a larger sample size we may be able to find out if the information found during this study will hold true in other areas.  Stay tuned!