Thomas Sepulchre

Karma: 564

Thomas Sepulchre 26 Sep 2023 16:05 UTC
1 point
0
in reply to: jefftk’s comment on: Fund Transit With Development
You get back to the point of projects being mutually exclusive. Can you elaborate in your example on why the projects would be exclusive?

Thomas Sepulchre 26 Sep 2023 14:07 UTC
1 point
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in reply to: jefftk’s comment on: Fund Transit With Development
Ok, let’s stick to this notion of expected value because it plays both for the land owner and for the transit system builder.
To get back to your post, the plan was to buy an area, build a transit system in the middle of it, then sell the rest at a higher price. If you fail to buy all the land you need (or at least enough of it), you may give up on the project, in which case the value of the land does not increase. So indeed, as the transit system builder, the viability of your project (and the profit attached to it) is linked to the probability that you indeed acquire the land you need (both the land to physically build the transit system and the land around to sell later at a higher price), as well as the price at which you will be able to buy the land first, and re-sell it after completion.
Now, if the land owner are correctly calibrated, and they correctly anticipate the odds of your project being a success, your expected profit on the sale of the land must be zero.
If, on the flip side, you expect to make a profit because the land owners will underestimate your ability to succeed, will not see you coming, not understand what you are trying to do, or something along those lines, then your strategy relies on the market not being efficient. If this is the case, I think this is a crux.

Thomas Sepulchre 26 Sep 2023 5:38 UTC
1 point
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in reply to: jefftk’s comment on: Fund Transit With Development
I don’t see your point. If you are saying that there are many nearby sites for transit expansion, then the owner of the land should not sell at a low price, because if any of those sites is chosen, the land value will go up.
If you are saying that there are many alternative sites across the country, then this is not relevant. Those projects aren’t mutually exclusive.
We have to keep in mind that the land owner will not profit from the project being completed once the land is sold, they will only profit from the sale itself. The rational move is either to keep the land in case a project goes through, or sell it at the future price because selling means giving up on potential future profit of the project going through.

Thomas Sepulchre 25 Sep 2023 16:36 UTC
1 point
−2
on: Fund Transit With Development
The idea is, the public transit company buys property, makes it much more valuable by building service to it, and then sells it.
This plan is unrealistic because it assumes that the owner won’t price the future value in.
Assume you try to do exactly that. Why would the current owner sell the land and the historic price when, in fact, it is very clear that the price will go up once you are done with your project? No, the owner won’t sell below the anticipated value of the land, or at least a substantial fraction of it.

Thomas Sepulchre 13 Sep 2023 18:43 UTC
24 points
19
on: Contra Yudkowsky on Epistemic Conduct for Author Criticism
I think one confusing aspect is the fact that the person being critical about the structure of the post is also the target of the post, therefore it is difficult to assume good intent.
If another well respected user had written a similar comment about why the post should have been written differently, then it would be a much cleaner discussion about writing standards and similar considerations. Actually, a lot of people did, not really about the structure (at least I don’t think so), but mostly about the tone of the post.
As for EY, it is difficult not to assume that this criticism isn’t completely genuine, and is some way to attack the author. That being said, maybe we should evaluate arguments for what they are, regardless of why they were stated in the first place (or is it being too naive?)
In that regard, your post is very interesting because it addresses both questions: showing that EY hasn’t always followed this stated basic standard (i.e. claiming that the criticism is not genuine), and discussing the merit of this rule/good practice (i.e. is it a good basis for criticism)
Anyway, interesting post, thanks for writing it!

Thomas Sepulchre 13 Sep 2023 17:42 UTC
2 points
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in reply to: aphyer’s comment on: Duty to rescue / Non-assistance à personne en danger
I think you are missing the point.
Getting back to the example about an old man collapsing in a bank lobby, let’s compare three alternative types of actions:
- Helping
- Doing nothing
- Harming an old man on purpose
Claiming that there is no meaningful difference between action and inaction would imply that doing nothing to help the old man is equivalent to harming an old man. This is indeed a fairly extreme position, and I agree with you that it is rejected by nearly everyone. In this very real case, the bystanders were fined by the German justice system for not helping, but they were not put in jail, as would have been the case for harming an old man (at least on purpose). So the German justice system agrees with you on this point.
But that’s not really the question of duty to rescue. The question is not about the equivalence of doing nothing and harming an old man, it’s about the equivalence between helping and doing nothing. In this case, one would be fined for doing nothing, but wouldn’t be fined for calling an ambulance.
Without the duty to rescue, one wont be fined, or otherwise punished, for doing nothing. This makes doing nothing a safe choice (at least in term of legal consequences).

Thomas Sepulchre 6 Sep 2023 14:09 UTC
4 points
1
on: Find Hot French Food Near Me: A Follow-up
‘Petard’ is French for ‘fuck you’
Is it though? Where have you heard that?
If we search for Pétard in google translate, the results are petard, firecracker, squib, cracker, banger, maroon, backfire, whizz bang, which doesn’t seem to match your definition. If we try Petard, google translate auto-corrects into Pétard so I’m assuming this is what you meant.
Maybe google translate doesn’t know swear words though? To check that, I try to translate Putain, which is a foul word for prostitute. I will not write the results here, but you can check for yourself that the results match this definition.
If we go the other way around, and try to translate fuck you, we get a french sentence which I won’t write here either, but perfectly matches the english sentence.
What evidence supporting this can you provide?
[EDIT] You may also want to check Pétard(homonymie) on wikipedia

Thomas Sepulchre 5 Sep 2023 15:56 UTC
12 points
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in reply to: johnswentworth’s comment on: Who Has the Best Food?
Shouldn’t this imply that a country with a huge colonial empire (and the UK comes to mind) would have the best food?

Thomas Sepulchre 5 Sep 2023 14:22 UTC
10 points
1
on: Who Has the Best Food?
I’m not really sure how useful this poll is to answer the title question of this post. Indeed, what is evaluated in each cell is the food labeled as “country A” in “country B”, which may or may not be similar to what one would find in country A.
For example, let’s consider the first row. It describes how much each country’s version of italian cuisine is liked within said country, but may not reflect how much anyone would enjoy the food, were they to travel to italy. In particular, I wouldn’t be surprised to see an italian traveling around the world, appalled or amused by what each country labels as italian food.

Thomas Sepulchre 1 Sep 2023 12:08 UTC
4 points
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on: A Golden Age of Building? Excerpts and lessons from Empire State, Pentagon, Skunk Works and SpaceX
I’m not sure I follow you on the skyscrapers example.
The Burj Khalifa is about 2 times higher, and took about 3 times as much to be built ; it doesn’t look like things are getting much slower. Even better, it is 2 times higher, thus it is between 2 times and 8 times bigger (depending on how scaling laws work for civil engineering), so one could argue that it was built faster.
The slowest example, the Abraj Al-Balt, also seems to be much bigger than the other ones, so it’s not too surprising either (?)

Thomas Sepulchre 31 Aug 2023 19:09 UTC
1 point
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in reply to: Holoraven’s comment on: Prizes for matrix completion problems
(I’m not the OP but) absolutely not. The problem is about incomplete matrices, and the idea is to get an upper bound linked to m, i.e. an upper bound linked to how incomplete the matrix is. If you rephrase the question 1 as O(n^3), this is a completely different question, because now you only care about how big the matrix is, not how complete it is.
Also, since question 1 can be achieved with some gaussian pivot in O(n^3), and it also implies being able to tell whether a matrix is PSD or not, I think the best known complexity wrt n is indeed O(n^3).

Thomas Sepulchre 8 Aug 2023 18:34 UTC
20 points
5
on: Perpetually Declining Population?
1.66 children per woman in the US
I want to stress that this is the total fertility rate (TFR), and not the completed cohort fertility (CCF), and therefore it is not a very good proxy for what you want to measure, especially since women are having children later. I wrote a post about it a while back, although it is far from perfect. You can also look it up on wikipedia or something similar.

Thomas Sepulchre 5 Jul 2023 7:44 UTC
6 points
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on: Dominant Assurance Contract Experiment #2: Berkeley House Dinners
I liked your first post and I like this second one. I hope your events succeed
Just to clarify:
- Is anyone invited to the weekly dinners (thus you are providing a public good)?
- Or, are the dinners limited to the contributors (thus it is a club good)?
From reading pu1377.dvi (gmu.edu), I believe that dominant assurance contracts work better for club goods
At least in the sense of “you receiving as much money as possible” or “the contract being more likely to succeed”, but obviously you may put value on welcoming everyone, and, in general, those two alternative dinners won’t be the same.

Thomas Sepulchre 5 Jul 2023 7:10 UTC
3 points
2
in reply to: Ilio’s comment on: Two Percolation Puzzles
I can see the smiley through the spoiler protection. This is eerie.

Thomas Sepulchre 27 Jun 2023 1:38 UTC
2 points
1
in reply to: bhauth’s comment on: nuclear costs are inflation
You are cherry-picking. From the wikipedia page list of commercial nuclear reactors, the duration between 1960 and 1980 ranged from 3 to 15 years. Only one plant (the one you cite) took 40 years to build, and only one other as far as I can tell took more than 30 years, out of the 144 entries of the table.

Thomas Sepulchre 27 Jun 2023 1:17 UTC
1 point
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in reply to: bhauth’s comment on: nuclear costs are inflation
I did read your post, but how high an inflation do you need to match this graph? If you argued that the inflation for nuclear plants is let’s say 1% or 2% higher than the inflation in general, why not. But a crude estimates gives an inflation of 30% per year to account for the increase shown in this graph. That’s unheard of.
You mention several times a 5% inflation figure. For a 5% inflation figure to explain this graph, it would take more than 40 years when the date of construction start is separated by only 8 years. So unless, within 8 years, the construction duration was increased by 30 years (which would already be concerning, and fuel the “this is a regulation problem” narrative), your explanation doesn’t match the data.

Thomas Sepulchre 27 Jun 2023 0:49 UTC
3 points
1
in reply to: Andrew Vlahos’s comment on: nuclear costs are inflation
From the same paper:
Inflation doesn’t explain a tenfold increase between ~1967 and ~1975. Regardless, this graph is in 2010$ so inflation doesn’t explain anything. I agree with @Andrew Vlahos that inflation doesn’t explain the trend.

Thomas Sepulchre 21 Jun 2023 14:48 UTC
1 point
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in reply to: jefftk’s comment on: Public Transit is not Infinitely Safe
Honestly I don’t really know

Thomas Sepulchre 21 Jun 2023 14:34 UTC
3 points
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in reply to: jefftk’s comment on: Public Transit is not Infinitely Safe
I agree with you that this gets pretty tricky.
One trip per day seems very low, don’t people usually do at least two trips per day (going to work, going back home), or even 4? Are trips bi-directional (in which case I must apologize, this would be a misunderstanding on my side)?
None of this is to discourage your request that such claims be supported by sources, as a standard.

Thomas Sepulchre 21 Jun 2023 12:16 UTC
3 points
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on: Public Transit is not Infinitely Safe
there were 0.71 driving deaths per 100M miles travelled
I don’t think this is a good basis for comparison. The comparison in the tweet you link to seems to talk about commuting, so it would probably make sense to compare based on the number of trips rather than based on the miles traveled. In particular, in the data you link to, we can see that the number of car accidents from trucks is pretty small, while I would guess that truck drivers represent a bigger share of miles traveled, thus lowering the death rate per mile, without this being relevant information.
[EDIT] I looked it up
For public transit, you write (for a high crime rate city, but not the highest possible, and for an outlier year, as pointed out in another comment)
This is 3.7 homicides per 100M trips.
In the US, there are about 400 billion car trips per year, and about 40k death per year, so this implies an average death rate of 10 death per 100M trips. This is an average.