Lots of people are linking to an article on observer.com noting that some fundraising emails from the Obama campaign are “deleting” mention of Sarah Jessica Parker. The piece on the New York Observer points in turn to a site set up by propublica that shows several variants of an email marketing campaign. So far they have collected 7 different variants.
This is nothing new. Marketers have been split testing email marketing messages since email’s inception. As much as I’d love to poke fun at Sarah Jessica Parker, there is simply nothing sinister going on – and the messages prominently featuring SJP may in fact be the best performing variants. In fact, if they are using a “
OneMulti Armed Bandit” approach to split testing the fact that the emails mentioning SJP have been spotted by propublica more frequently than the other variants *may* show her mails are performing better. Of course the sample size in this case is of extremely limited value.
I’ve recently been spending most of my time split testing the designs across many of the sites I manage. The question is always raised – how will this effect my seo? Unfortunately website owners aren’t allowed to serve up different page versions to search engines than to regular visitors – without risking the wrath of Google. (That is unless you’re one of the big brands) This technique is commonly referred to as “cloaking” and is expressly in violation of Google’s webmaster guidelines.
Luckily we have a new tool at our disposal to set things straight with some level of reliability – the link canonical tag. According to Google:
If your site has identical or vastly similar content that’s accessible through multiple URLs, this format provides you with more control over the URL returned in search results. It also helps to make sure that properties such as link popularity are consolidated to your preferred version.
Let’s assume three split test variant pages:
To properly point each page to the original you would simply place this tag in the HEAD statement of each page:
<link rel="canonical" href="http://www.domain.com/index.php">
What about other search engines you say? Well luckily Yahoo! and Bing announced support for the link canonical tag at the same time as Google. YMMV with these second-tier search engines – but at least they have stated their intent to honor it.
A second level of protection can be added by adding a meta tag to each page to prevent indexation. I would recommend a setting of NOINDEX, FOLLOW as seen below:
<meta name="robots" content="NOINDEX, FOLLOW" >
Obviously this method is ONLY going to work if you are split testing and not multivariate testing.