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Tree testing certainly does not take the place of usability testing. Think of tree testing rather as a complement to usability testing - a early way of testing structural ideas before you we even have a prototype.
It's also good to know that that tree-testing results line up nicely with later usability testing, as described in this 2014 academic paper.
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Analytics are great because they tell you us what your our total population of site visitors is actually doing on your our site – where they click, where they don’t, and so on.
The traditional weakness of analytics is that, while they can tell you us (in detail) what actions your our users are taking on your the site, they can’t tell you us why. When you we track visitors jumping from your our home page to an intermediate landing page to a content page, you we have no idea why they’re going there; maybe they’re looking for what you we intended, maybe they’re not. Maybe they leave because they found the answer they wanted; maybe they leave because they didn’t. You We have no context, so you we don’t know how well the site performed in that sense.
Like a usability test, tree testing gives you us context by letting you us set specific tasks for the user to do. When they go down a certain path in your our tree, you we know if that’s a success or a failure.
Analytics are a great way to see where your our users are going, and can reveal issues in your our site structure, but on their own they’re not enough.
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