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jeffbradberry

24 karma · joined July 21, 2009

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jeffbradberry··on Ask HN: Is there anyone here who still uses slide rules?
What I _really_ want, now that I have the Faber-Castell, is a Curta.

https://en.wikipedia.org/wiki/Curta

jeffbradberry··on Ask HN: Is there anyone here who still uses slide rules?
I have four now, and even go out of my way to use them a bit.

My favorites from my collection are a little Dietzgen No 1773, which is surprisingly featureful for something that can fit in a pocket, and a Faber-Castell Novo-Biplex 2/83N, which is kind of one of the big guns for slide rules.

jeffbradberry··on 417-megapixel Andromeda galaxy panorama took over a decade to make
That is not accurate -- the Andromeda Galaxy is over 3 degrees wide. About 6 full moons.
jeffbradberry··on The Quadrantid meteor shower 2024 peaks tonight alongside a bright moon
This seems like a cool concept, but it's broken for me.

Firefox 113.0.2 shows the orbits and background, but no particles as far as I can tell.

Chromium 120.0.6099.129 shows just a black screen plus the widgets, nothing else.

Both on amd64 Debian Linux.

Update: bumping FF to 121.0 did not seem to help.

jeffbradberry··on A Romanian economist legally gamed the lottery
There is a fixed probability of matching all numbers but the value of doing so varies, so sometimes the EV can be positive.
jeffbradberry··on The cursed computer iceberg meme (2021)
Here it is as a pdf: https://rifters.com/real/shorts/VampireDomestication.pdf
jeffbradberry··on The cursed computer iceberg meme (2021)
This should be the page, but it requires a Flash plugin (so doesn't work for me): https://rifters.com/blindsight/vampires.htm
jeffbradberry··on How to become haunted by path dependence
Sounds like https://en.wikipedia.org/wiki/Expedition_%28book%29
jeffbradberry··on Iceland’s psychedelic Stonehenge
http://www.thefoamhenge.com/
jeffbradberry··on Wow, Perl 6 [video]
It looks like revealjs.
jeffbradberry··on Introduction to Monte Carlo Tree Search
In what appears to be the originating paper for UCT ("Bandit based Monte-Carlo Planning", L. Kocsis and C. Szepesvári, 2006),

* The choice of action to be returned is the one "with the highest average observed long-term reward"

* For simplicity, the payout value used in the paper is 1=win and 0=loss, which will result in the agents maximizing their wins. Presumably one could choose other payout values (i.e. points for that player in games that have that concept) to adjust the priority of the agents. The mathematics does not seem to forbid it.

* This paper uses as their first experiment a multi-player game. They state, "...for P-games UCT is modified to a negamax-style: In MIN nodes the negative of estimated action-values is used in the action selection procedures." It is straightforward and more generalizable to games with N > 2 players to simply record values from that player's standpoint in the first place, instead of manipulating it after the fact in this manner.

I hope this clarifies some things.

jeffbradberry··on Introduction to Monte Carlo Tree Search
Excellent. I did want to eventually write something showing how to modify this algorithm to handle games with randomness, and ISMCTS at a glance looks like it does just that. Thanks!
jeffbradberry··on Introduction to Monte Carlo Tree Search
I've updated the diagrams with a set of node values that (hopefully) make sense.
jeffbradberry··on Introduction to Monte Carlo Tree Search
Since the win counts are only incremented for nodes "moved into" by the winning player, UCB does correctly model the opponent's behavior here.
jeffbradberry··on Introduction to Monte Carlo Tree Search
Actually, I think it should be 3/8, since it's supposed to be the opposing player's win count.

These diagrams were supposed to just be an update of the diagrams from the MCTS Wikipedia article, adding the correct backpropagation values, but I see there are more problems than that.

jeffbradberry··on Confessions of a Git Skeptic
A fair point, but in practice I get fellow engineers trying to quote the sequence numbers at me.
jeffbradberry··on Confessions of a Git Skeptic
I don't understand this obsession with sequential commit numbers. These may vary from repo to repo depending on your commit/pull history.
jeffbradberry··on Stephen Hawking outlines three theoretically realistic ideas for time travel
-1 (if I in fact had the points to do it), for assuming that changing the metric space obviates calling a dimension a dimension.
jeffbradberry··on Facebook now posts strangers' stories in your feed...
I have to mark this one "cannot replicate". I see no sign of this behavior on my account.
jeffbradberry··on 45 Astonishing Examples of Long Exposure Photography
I found it impressive, and I've seen content here on HN that is less relevant than this.
jeffbradberry··on Nomic: "...a game in which changing the rules is a move."
Not at all in any of the variants I know of.
jeffbradberry··on Ask HN: Back in time to 100 BC, what knowledge would you impart to the people?
There's a great little story by L. Sprague de Camp called "Lest Darkness Fall" that is almost exactly this. An archaeologist from the 1930s gets stuck back in the 6th century A.D., and "invents" the printing press (among other things).
jeffbradberry··on Euclid, Schmeuclid
Exactly.
jeffbradberry··on Ask HN: What is your favorite board game and why?
Settlers (and Seafarers, and Cities & Knights) of Catan is a great game. My girlfriend and I also like Ingenious. It's a very simple and quick game (and the only one I've found that's still interesting with two players), yet there is some fairly interesting strategy to it.
jeffbradberry··on Mourning the Death of Handwriting
This article seems to be claiming that computers and text messaging are responsible for the final decline in handwriting, but I grew up before personal computers were ubiquitous (I was born in 1977) and cursive was already heavily deemphasized in the schools I went through. I don't recall a single teacher who wouldn't accept hand printed work.
jeffbradberry··on Apparently AT&T has started blocking 4chan
I have DSL through AT&T, yet img.4chan.org/b/imgboard.html does not appear to be blocked for me. Perhaps there is some other problem at work here?