Split Testing and Return Visitors

Just a quick post about a phenomenon I’ve personally seen happen but don’t recall ever seeing mentioned in split testing articles.

I’ll start by saying that ideally you should always look at the results from any split test by segmenting your visitors.

It’s not enough to know that overall version X did better than version Y. Ideally you should check how the different versions performed for various visitor segments. For example, users from organic search might behave differently than visitors from a referring site or direct traffic.

There is one segment though where merely the fact that you’re doing a split test can have an impact on the results:

New vs. Return visitors

Even if you weren’t doing a split test, you would probably see a difference between the two segments based purely on the fact that return visitors already know something about your product, service or site.

I’m talking about a different phenomenon though. The “something has changed” effect.

For new visitors, your site will be new regardless of which version of a test page they see.

For return visitors who have some level of familiarity with your site, if they see something new or changed on the site, they’ll probably pay more attention to it – merely because it’s different.

For example, if you’re homepage does not currently have any video on it and you test a new version with some video on it, return visitors who get the version with the video might watch the video simply because it’s something new.

Conclusion: Always segment visitors by new and return visitors.

If both groups show the same preference, it’s safe to say that you have a winner. If you’re seeing a large variance between new and return visitors, it might be worth it to let the test run for a while to see if the variance changes over time as more of the return visitors first visited the site after the split test started.

[UPDATE]
I was just thinking that this would be a feature that split testing tools can / should support. Segmenting not only new vs return users, but return users who’s first visit was before the split test started vs return users who’s first visit was after the split test started.

Heck – you should be able to only include visitors who’s first visit was after the test started if you want to. Are you listening optimizely, visual website optimizer, and the rest of the gang?

Is Above The Fold Still Important?

A couple of weeks ago user experience guru Jacob Neilson wrote an article about user attention above and below the fold.

In a nutshell he says:

… users will scroll below the fold only if the information above it makes them believe the rest of the page will be valuable.

I totally agree.

On the other hand, a few people have pointed out to me a recent article by CX partners in the UK that states the fold isn’t very important anymore. They say:

We see that people are more than comfortable scrolling long, long pages to find what they are looking for. A quick snoop around the web will show you successful brands that are not worrying about the fold either.

I was thinking about the two articles which seem to be contradictory. After digesting all of the data, I have to say that both parties are right – they are just missing a crucial piece of information – the context in which the visitor is viewing the page.

If I’m on Amazon.com viewing a list of products, of course I’ll scroll because I know the information I want is below the fold.

If I just clicked on an ad and have landed on a site or page that I have never viewed before, my first internal question is “am I in the right place” and only after my internal dialog says yes, will I think “do I need to scroll to find what I am looking for”.

In the second scenario, it’s crucial to have above the fold all of the information the visitor needs in order to know they are in the right place.

So, in summary, if we combine the two opinions and add the missing ingredient – context, we get this (my version):

People are more than comfortable scrolling long pages only if the information above the fold, or their existing knowledge, makes them believe the rest of the page has what they are looking for or will be valuable.

On a side note, the CX partners article does indeed address the issue of bad design leading to a user not scrolling due to them not realizing there is more information below the fold, but that’s a different scenario.