Hey all,
This Friday, Trey Jones (our awesome Relevance Engineer) and I spent some time playing detective with the sampled request logs and a list of the most common queries resulting in zero results. We found a lot of interesting things. In particular:
1. A common pattern in which queries, for no particular reason, had a UNIX timestamp preceding them (example: "1436336857594:2019 FIFA Women's World Cup"). This is responsible, on its own, for 3% of zero results queries - and it appears to be caused by the Wikimedia Apps. 2. A search for strings in quotes followed by 'film' (example: ""Seventh Son" film"). This is caused by a media player and is responsible for around 0.5% of zero results queries. 3. A search for "quot" strings (example: " quot James Tree quot"). This is from the National Library of Australia and is again around 0.5% of zero results queries. 4. A search for a page title and the name of a page that appears as a link within that page (example: ""2C-T-19" AND "JWH-081""). This is about 6% of queries and appears to come from a German IP address. We're unaware of who this person is or what they're trying, so if anyone knows what on earth this is, we'd appreciate the hint ;).
https://phabricator.wikimedia.org/T107724 is a card representing the need to reach out to these people, where possible (obviously this will be easier for the app team than anyone else ;p). If we can get all of these solved for, we could drop the zero results rate for full text by about 10% Obviously cutting /all/ of it out is improbable, but we're hopeful that we can drop this number and get a better understanding of what third-party users are trying to achieve, to boot.