When any webmaster first enters the realm of SEO, they’re likely to run into the term “Google algorithm.” The Google search algorithm is a complex mathematical equation that looks at more than 100 metrics to determine how a site should rank. Beyond being a non-public and thoroughly complicated equation to begin with, Google changes the weight and presence of metrics on a regular basis.
In fact, last year over 500 changes were made to the search algorithm. These changes ranged from minor tweaks to all-new user interface presentations to notable alterations to the relevance of certain ranking factors.The frequency of the changes often leaves webmasters confused and frustrated. Luckily, while Google’s algorithm is secret, their process is not.
Amit Singhal, Google Fellow, introduced a breakdown of the process used to test and implement the algorithm changes. Google ranking engineers are the first to touch the issue, examining under-performing searches and coming up with ideas on what could be done to improve the user experience. Any idea that seems reasonable is tested with a select group of raters who give initial feedback on whether the results have really improved.
Google then moves the project to a “sandbox,” an experimental version of the search site that’s shown to only a small cut of visitors. An analyst who is assigned to the test then looks through the user responses, feedback, and metrics to see if there seems to be an improvement. The data is then compiled and brought to the Google evaluation team, who decides whether or not the change should launch.
Last year, only 1 out of every 40 presented changes were approved. For that reason, it’s a good idea to take information about experiments with a fairly large grain of salt.