This may seem a bit ‘back to basics’, but it’s a topic of discussions I’ve been having recently.
When presenting performance metrics, folks sometimes use mean, sometimes median, sometimes both, sometimes they include standard deviation, percentiles, etc. I’ve been looking for some concrete guidance on what metrics to use, and in what contexts.
There has been a good deal of work around defining guidelines, best practices, etc. for improving Web page performance (i.e. delivery speed). As Web page publishers have worked to implement these best practices, they inevitably reach a point where they can go no further to improve their own content. The long poles in the tent are outside their control, often in third-party content – in many cases, ads.