Alexa Overhauls Ranking System
Everyone's favorite web statistics whipping boy Alexa has announced a major overhaul of how it compiles traffic figures. — The biggest change is Alexa's decision to drop exclusive reliance on the Alexa toolbar for traffic data, with Alexa now aggregating data from …
Context & Ripple Effects
Alexa had already added geographic traffic-source detail pages, while criticism held that its rankings could mislead assessments of web-service growth and reach. The April 2008 overhaul shifts attention from extra reporting features to the underlying data used to produce the rank.
Ending exclusive reliance on toolbar data directly addresses the central weakness behind the critique of Alexa as a measure of reach: a ranking is only as representative as the audience data behind it.
First-order effects
- Alexa's rankings will no longer be determined solely by its toolbar panel, creating a break in comparability for publishers and web services that cite the figures over time.
Second-order effects
- Users relying on Alexa to compare web-service growth and reach must separate movement caused by the new methodology from movement caused by underlying audience changes.
Third-order effects
- Alexa's overhaul, alongside Nielsen's 2007 ratings adjustment, makes collection methodology a more visible competitive attribute for web-measurement providers rather than a back-end implementation detail.
The trend: Web measurement is moving away from single-source audience panels toward broader data collection, making the credibility and transparency of ranking methods part of the product.