1 HN user recommended this talk1 month2017–2023score 1
Years with an HN recommendation, 2007–2026
It is the go-to primary source whenever HN discusses posits versus IEEE floats, valued for Kahan's sharp critique despite the poor audio.
A 95-minute recorded debate at the ARITH23 computer arithmetic conference between John Gustafson, proponent of unums/posits, and William Kahan, architect of IEEE 754 floating point. They argue the merits of the new number formats versus conventional floats and interval arithmetic.
“Audio quality is not great but there are links to slides from Gustafson and Kahan” (HN, 2017)
The Great Debate @ARITH23: John Gustafson and William Kahan [this video] Audio quality is not great but there are links to slides from Gustafson and Kahan
Debate between Gustafson and Kahan on unums versus floats
I did some reading on unum a while back, inc. Kahan's criticisms. There's another side. There's a vid on youtube with Kahan and Gustafson talking over it. Kahan goes in like a wolf onto a lamb, much to gustafson's shock and hurt. Gustafson points out some of Kahan's criticisms are plain wrong, even citing the page in the book, then says something like "we should be working together on this, why aren't we working together?" Kahan doesn't respond. Kahan may be right or wrong but his attitude is weirdly hostile, and Gustafson is no n00b about floats. Edit: I think this is it (but it's been a while) [this video]
Kahan criticizing Gustafson's unum work in a hostile debate
Original posits are variable width, making them nearly useless for high performance parallel computations. Later versions don't add anything of use for low precision neural networks, and lack of hardware support anywhere make them too slow for anything other than toying around. See also [link] and [this video]
A related discussion about number types: The Great Debate @ARITH23: John Gustafson and William Kahan [this video] Kahan points out disadvantages of interval maths.
Kahan explains disadvantages of interval math in debate
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