Bounce Rate Illusion
This is a measurement artifact that can occur when A/B testing website speed. "Bounce rate" refers to the percentage of visitors who leave a site after viewing only one page. A faster page sends analytics tracking signals more quickly and reliably. This means that for users who were going to bounce anyway, the faster page is more likely to successfully report that bounce before the user leaves. Paradoxically, this can make the faster group in an A/B test appear to have a slightly higher bounce rate, even though the user experience was better. This "illusion" is simply a result of more accurate tracking.
Related web performance terms
- Back/Forward Cache (bfcache)
The back/forward cache (or bfcache) is a browser optimization that enables instant navigations when a user clicks the back or forward buttons.
- Backend
The backend refers to the server-side components of a web application that are not visible to the end-user. This includes the web server, application logic, and databases.
- Backend Cache (AWS)
This is Speed Kit's central, primary cache where Anonymous HTML and other website assets are stored. It is hosted on Amazon Web Services (AWS), a secure and highly reliable cloud computing platform.
- Backend Time
Backend Time is the duration it takes for a website's Origin Server to process a request and generate the HTML for a page.