The practical summary of Latent Dirichlet Allocation for SEO

What’s the hottest trend in search engine optimization that you’ve never heard of (yet)? The folks over at SEOmoz have been doing a great series on Latent Dirichlet Allocation (LDA), which is a context-based algorithm for determining search relevance. Their research has shown strong correlation between LDA and search rankings. However, it’s little things like this:


Photo credit: SEOMoz

…that make people flee in terror from LDA, and who can blame them?

So here’s what you need to know about LDA as it relates to search engine optimization:

Your content has to be about something and worth reading.

Huge surprise, huh? Google has said for years that its stated aim is to get search engine rankings in alignment with “human rankings” – that is, if the content is valuable to a human being, it should rank well. If the content isn’t valuable to a human being, then it should rank poorly. For years, Google has used PageRank and inbound links as proxies for judging the value of content, but now there’s a theory in the SEO community, supported by the SEOmoz data, that on-page content may play more of a role in your rankings than previously thought.

What makes this different from the early years of SEO is that it’s somewhat harder to game. Instead of simple on-page optimization tricks that Google can devalue quickly (bold text, H1 titles, etc), the LDA algorithm looks at the total picture of the content and its context. Does a web page talking about World of Warcraft mention paladins, death knights, and fish feasts, or is it just badly repurposed, valueless content surrounded by gold spam ads?

So how do you make use of this knowledge? Here are three immediate to-do tasks:

1. Make sure you are using the rel=canonical tag.

Use this tag in your web site, blog, and any place where you have ownership of your content. As more and more algorithms are tuned to contextual content, the reward of ripping off someone else’s content will be much greater, so using this tag will help at least assign some level of ownership to stuff you write. If you’re using WordPress, the All In One SEO plugin will do this for you automagically. Want to learn more about this tag? Read what Matt Cutts of Google has to say about it.

2. Make your web site about something.

A personal blog is fine to be all over the place, one day talking about cooking, the next day talking about Twitter, etc. A professional blog and/or your corporate web site has to be about something and needs to have lots of original, high quality, on-topic content using semantically related words in the copy that correlate to the search terms you’re going after. For example, Blue Sky Factory’s new web site (shiny!) has a TON of new content that talks about email marketing in all of its various aspects, using all of the different ways people talk about it. You can’t get away with two sentence pages and minimally valuable content any more – you have to do the hard work of creating good stuff in order to leverage this algorithm effectively. That’s why we’re seeing strong correlations between the LDA algorithm and Google’s results – Google wants to continue rewarding valuable content and making life harder for lazy SEO folks.

3. Stop feeding the social media machine all your stuff.

This one will be controversial but true. It’s perfectly okay to have conversations, to engage, to be interesting on Twitter, Facebook, LinkedIn, etc. but I want you to stop putting your best stuff there in full. Why? Because this algorithm is all about quality AND quantity of content. If your blog or website is gathering dust while your Facebook page is bursting at the seams, you’re doubly harming yourself. Not only are you making yourself dependent on an entity that doesn’t give a rat’s ass about you, but you’re penalizing your own web site/blog by not having context- sensitive information on it. Keep sharing, keep linking, keep conversing, but don’t give the keys to your kingdom – your content – to the social media sites. Excerpts? Fine. Full blog posts? Not so fine. Teasers from eBooks? Fine. Large chunks of copy? Not so fine.

Is LDA a game-changer as many say? Maybe it is, maybe it isn’t, but if you follow the practice of creating lots of original, great stuff on properties you own, you’ll never go wrong.


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  • http://www.grizzard.com/author/epratum/ Eric Pratum

    I was at the SEOmoz seminar when Ben Hendrickson presented that. Not only was his back and forth with Rand hilarious, but the attendees erupted in applause several times during his talk. Ben’s presentation of that and his relevancy tool was quite impressive and valuable for future planning of content roll outs.

  • http://twitter.com/rhcerff Robert Cerff

    Point 3 is about as good as it gets. I can’t believe how many people don’t realise just how valuable their content it and just how they are giving it away, to those that don’t give a rats-ass!

  • http://twitter.com/ACTeeple Amy C. Teeple

    I think the “scary equations” kept me from paying attention to this topic previously, but as a copywriter, I am glad that I found your post (via SEO Copywriting blog). This is great news and awesome information/advice. Of course, I agree that you need good, relevant content – I’ve been saying that for years (of course I was – I sell writing services). However, I must also wholeheartedly agree with point #3. Why let Facebook get all of your traffic. Use your Facebook page to funnel your audience back to your website.

    Thanks for this post! Good stuff (even if I am a little late finding this).

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