> Is "A.I." NYT house style? Looks rather jarring.

I think their style is to use periods for acronyms, which I believe is traditional. A quick scan of their recent headlines turns up "U.S", "A.I.", "A.T.M.", "ICE", "L.P.G.A.", "REI", "U.K." I don't know what the reasoning behind the use of "ICE" and "REI" is, could be a mistake or a judgement that those words are tend to not be understood as acronyms, or something else.

IIRC they used to always style "NASA" as "N.A.S.A." even though the agency itself never uses periods and is of course always pronounced as a word rather than initials. (This particular example stuck in my mind just because I work there). Hopefully "ICE" and "REI" reflect a change in that style to omit periods when referring to organizations that omit the periods in their own style guides.

I don’t think this has been true for the vast majority of NASA’s existence. [This 1966 NYT article about Gemini](https://www.nytimes.com/1966/03/20/archives/gemini-8-mishap-...), [this 1986 article about Challenger](https://www.nytimes.com/1986/09/22/us/nasa-had-solution-to-k...), and [this 2010 article about Constellation](https://www.nytimes.com/2010/05/27/science/space/27nasa.html) all omit periods. Even if NYT did stylize it as “N.A.S.A.” in its earliest articles, this would not diverge from common agency practice early on. For instance, in [this official reel about the dedication of Marshall Space Flight Center](https://www.youtube.com/watch?v=4fasslw4MvE), it is pronounced spelled-out as four letters.

Looks to me like initialisms get periods unless they are acronyms or trademarks. So "ICE" is fine because it is read as "ice" and not I.C.E. (eye-see-ee). REI is not an initialism though, but presumably they have kept it as-is because it's their trademark/"doing business as" style.

That is correct and also how everyone else should be using the English language.

The “REI” initialism, is the official d.b.a. for the Recreational Equipment, Inc. company.

Erratum: I meant to say that REI is an initialism but not an acronym

Artificialïntelligence

This is the NYT, not the New Yorker