Kyle Risley

Nice find, Glenn. "When Google doesn't know the quality or popularity of a URL, it uses the aggregate for its parent path. Then that path's parent, and so on." Let's connect that to the DOJ findings and attributes we know of from leaks (my own logical inference ahead): "When Google doesn't know the quality (Q* Quality) or popularity (P* Popularity) of a URL (T* Topicality), it uses the aggregate for its parent path (NSR). Then that path's parent, and so on (predictedDefaultNsr)." New Site Rank (NSR) - an attribute from Google leaks - specifically, predictedDefaultNsr operating across subchunk path hierarchies - is one of the exact mechanisms behind the parent-path fallback behaviour. It solves the "cold start" problem for new or low-data URLs. When Google lacks sufficient engagement or page-specific data for a page, it assigns a default predicted score computed by aggregating signals from higher structural levels (parent paths and host level). The fallback value is driven by predictedDefaultNsr through the subchunk hierarchy, but the confidence weight Google applies to that fallback depends on siteQualityStddev (Standard Deviation). The leaked API also contains rhubarb, defined as a "Site-URL delta signals based quality score." While a new URL inherits its baseline from predictedDefaultNsr, the system actively measures how far the page strays from its parent path's baseline once crawled. This means inherited authority provides the initial entry score, but the page-level delta score quickly overrides it if the document is thin or low-quality. This is what "Domain Authority" actually is - and why it is easier to SEO a site with a lot of online business reputation than a new site. Domain Authority is an emergent property of New Site Rank’s structural fallback system. It is the aggregate site-level baseline (Q*and P*) that leaks downward through parent path subchunks to give newly published URLs an instant head start or a severe drag. I'll caveat this with this: Google's ecosystem is incredibly layered; while predictedDefaultNsr heavily drives what the industry calls DA, it likely interacts with other host-level signals (like sitewide NavBoost/click data and Chrome user data) to create the full "authority" effect. Let's not forget PagerankNS. My hypothesis therefore would logically be: Domain Authority is predictedDefaultNsr.