#052
Sep 15, 2019
Work
Tired of Elasticsearch 5 not supporting the rank_eval API, I wrote a script which would query our search and compute the metrics, enabling me to directly compare ES5 and 6. This let me do some experimentation to figure out which bits of the query contribute most significantly to the search result quality and, surprisingly, I found that it was phrase matching. In retrospect this makes sense because, while there are many searches which don’t benefit from phrase matching, there are enough searches for common phrases like “income tax” or “vehicle tax” which do.
We stopped the current search A/B test, which showed a difference of 1.86 percentage points between ES5 and 6, and started a new one with another tweaked query, which takes phrase matching into account. If this is even better, great; if not, the old query we had was probably good enough for us to go ahead with the switch to ES6.
I started work on a change to make quoted query fragments required, giving our search a more Google-like behaviour. Barely any people use quotes in searches on GOV.UK, so it may not get a lot of use, but it’s not too tricky to implement and I think it will benefit the people who do. And maybe more people will start to use quoted searches once they start to behave differently.
My team are trying a remote sprint, we’re working from home until Wednesday next week. I’ve rapidly turned into even more of a hermit than usual.
Miscellaneous
I started reading Metro 2033 (by Dmitry Glukhovsky), which is the basis for the game of the same name. It’s set after a nuclear war rendered the surface uninhabitable, and survivors live in communities in the Moscow metro system, living off mushrooms, and defending themselves from mutated surface creatures which occasionally find their way inside.
I’ve been reading the Ars Magica source books, I’m considering starting up a game of that once my Call of Cthulhu campaign ends—though that won’t be for a while, I estimate it’s got 10 or so sessions (20 weeks if everything is done on time) remaining. I really like the look of the magic system in Ars Magica, it feels more like actual magic is supposed to be than in most games.