trentmkelly/LessWrong-43k huggingface dataset:
Variadic functions in Hindley Milner
by philh — 2022-04-02T20:00:03.972Z

Note: math didn't transfer to LW. You might find this easier to read on my blog.

I previously mentioned an interest in adding variadic functions to Haskenthetical, the "Haskell with a Lisp syntax" I'm vaguely working on.

It sounds difficult. This is an attempt to figure out just how difficult, partly by looking at the state of the art.

A variadic function is one which can accept argument lists of different length. A well-known example in many languages is printf. Here are a bunch of functions I might want to be variadic in Haskenthetical, along with examples in Haskell of types I might want to use them as:

+, accepting any number ≥ 2 of numbers and returning a number of the same type.

(+) :: Num a => a -> a -> a
(+) :: Num a => a -> a -> a -> a

Similarly, -, * and /. - and maybe / could reasonably accept ≥ 1 input, but that would be inconsistent and disallow (- 3) as a partial application. - and / would be left associative, i.e. (- 5 1 2) would be (- (- 5 1) 2).

list, accepting any number of arguments of the same type and returning a List of that type. (An empty (list) would have type List $a, the same as Nil.) There's a related function that I'll call list' for now, where the final argument has to be a List and the other arguments are prepended to it.

list :: [a]
list :: a -> [a]
list :: a -> a -> [a]

list' :: [a] -> [a]
list' :: a -> [a] -> [a]
list' :: a -> a -> [a] -> [a]

I already mentioned printf. Haskell's implementation is in the Text.Printf module:

printf :: String -> IO ()
printf :: PrintfArg a => String -> a -> IO ()
printf :: (PrintfArg a, PrintfArg b) => String -> a -> b -> IO ()
-- Also: all of the above, with `-> String` instead of `-> IO ()`. But
-- that's not super relevant here.

» and «, which take a function and then ≥ 2 arguments to interleave it with. Currently implemented as macros, and maybe I'd want them to be macros even if they could be functions, but that's not the point right now. Often the function will have a type like -> $a (-> $b $a) or -> $b (-> $a $a), and then all or all-but-one of the arguments will be of the same type - this will be equivalent to using haskell's foldr or foldl. But that's not required. You could have (» , 1 "foo" 3

...
Book review: Very Important People
by Richard_Ngo — 2022-04-02T19:00:03.567Z

New York’s nightclubs are the particle accelerators of sociology: reliably creating the precise conditions under which exotic extremes of status-seeking behaviour can be observed. Ashley Mears documents it all in her excellent book Very Important People: Status and Beauty in the Global Party Circuit. A model turned sociology professor, while researching the book she spent hundreds of nights in New York’s most exclusive nightclubs, as well as similar parties across the world. The book abounds with fascinating details; in this post I summarise it and highlight a few aspects which I found most interesting.

Here’s the core dynamic. There are some activities which are often fun: dancing, drinking, socialising. But they become much more fun when they’re associated with feelings of high status. So wealthy men want to use their money to buy the feeling of having high-status fun, by doing those activities while associated with (and ideally while popular amongst) other high-status people, particularly beautiful women.

Unfortunately, explicit transactions between different forms of cultural capital are low-status - it demonstrates that you can’t get the other forms directly. So the wealthy men can’t just pay the beautiful women to come party with them. Instead an ecosystem develops which sells sufficient strategic ambiguity to allow (self- and other-) deception about the transaction which is taking place, via incorporating a series of middlemen.

Specifically, wealthy men pay thousands at these nightclubs for table charges and “bottle service” - already-expensive alcohol marked up by 5x or much more. The nightclubs pay “promoters” to scout out and bring along dozens of beautiful women each night. Those women get access to an exclusive venue with many wealthy men - but by itself that’s not enough to motivate regular attendance, at least not from the prettiest. And most are careful not to ruin their reputations by actually accepting payments from the promoters. Instead, in order to bring enough girls, promoters each need to do a bunch of emotional labour, flirting, relationship-building, and many non-cash payments (food, transport, even accommodation). I’m strongly reminded of Michael Sandel’s book What Money Can’t Buy - the intuitions about the corrosive effects of money are the same, they're just applied to a much less high-minded setting.

Some interesting features of this ...
Real biosafety is socially inconvenient
by ChristianKl — 2022-04-02T18:50:58.615Z

Marc Lipsitch and Thomas V. Inglesby wrote back in

2014

:

However, research that aims to create new potential pandemic pathogens (PPP) (

1

)—novel microbes that combine likely human virulence with likely efficient transmission in humans—is an exception to that rule. While this research represents a tiny portion of the experimental work done in infectious disease research, it poses extraordinary potential risks to the public.

[...]

Multiplying the probability of an accidental laboratory-acquired infection per lab-year (0.2%) or full-time worker-year (1%) by the probability that the infection leads to global spread (5% to 60%) provides an estimate that work with a novel, transmissible form of influenza virus carries a risk of between 0.01% and 0.1% per laboratory-year of creating a pandemic, using the select agent data, or between 0.05% and 0.6% per full-time worker-year using the NIAID data.

Estimating risks of gain-of-function research this high is deeply awkward. When I spoke about the numbers with a local EA, his reaction was "this can't be true and has to be wrong". His reaction was emotional. When Marc Lipsitch was talking about reducing

catastrophic risk at EA Global

he left out being explicit about this risk from gain of function research and went more meta. In the environment of EA global, that's a much better status move because actually talking about his risk numbers would produce emotional pushback.

The Chinese recently called for more public transparency for military biological research in the US. Siding with the Chinese in their call for more public transparency for military biological research is socially awkward, so even people like Zvi who generally pro-biosafety and pre-independent thinking called the

Chinese position

a "nonsensical demand".

Given that the Biological Weapons Convention banned the development of biological weapons and the US signed it, you might ask yourself why the Chinese might have reasonable concerns about military biological research in the US. The US government interprets the convention very narrowly when it comes to its own activities. The convention allows for defensive research and the US government sees their research as defensive in nature.

One example of defensive weapons research was to modify anthrax to evade a vaccine response. According to the FBI, those modified anthrax strains were used in 200...
How I repeatedly failed to use Tobit modelling on censored data
by abstractapplic — 2022-04-02T18:10:42.063Z

This is a description of my work on a data science project, lightly obfuscated and fictionalized to protect the confidentiality of the organization I handled it for (and also to make it flow better). I focus on the high-level epistemic/mathematical issues, and the lived experience of working on an intellectual problem, but gloss over the timelines and implementation details.

In which our protagonist identifies the nature of the problem

Once upon a time, I had a client who wanted to win some sealed-bid, first-price auctions[1].

Or, to be more specific, they were winning some sealed-bid, first-price auctions; what they wanted was to win more of them more cheaply. To that end, they asked me to produce a model predicting the market price for future lots. I was provided a dataset containing various details of the lots sold in past auctions, as well as the winning bid for each of them, and told to get to work.

. . . you see the issue? If not, that’s gratifying, because it took me an embarrassingly long time to notice. Let me spell it out.

The dataset told me the winning bid for each auction even if my client won that auction. In other words, building an ordinary regression model on the entire dataset would lead to them trying to outbid themselves, missing opportunities to lower the price from whatever they bid previously. Worse, I knew my modelling work would be used as the blueprint for future models, potentially leading to a feedback loop: “this type of lot has become 5% more expensive” -> “let’s increase our bid 5% to make sure we win it” -> “this type of lot has become 5% more expensive”, etc.

But the auctions my client won weren’t completely bereft of useful information: their winning bids provided an upper bound on what the market thought those lots were worth (i.e., the highest bid from a source other than my client couldn’t be more than my client’s winning bid). And ignoring those rows of data entirely would introduce selection biases, as well as limiting their ability to predict price for that subset of lots.

In which our protagonist selects an angle of attack

Maximum Likelihood Estimation is the reasoning that underpins conventional regression[2]: multiply probabilities of the responses observed to get the joint probability of everything you see, then adjust your model to maximize that quantity. Tobit modelling is the generalization of MLE to datasets wher...
Noobs Need Rules
by Jacob Falkovich — 2022-04-02T17:56:08.236Z

Cross-posted from Putanumonit.

If you ask someone who’s good at dating for dating advice they’ll often tell you to “just be yourself”. Since they themselves are good at dating, being themselves serves them well. But if your self isn’t good at dating, you should probably be less yourself and more like the self of one of those people who are good at dating.

Many such cases.

Here’s a general model I propose of how people learn most skills:

At first, you can neither perform the skill or discriminate between good and bad performance.
You learn concepts that allow you to discriminate, and explicit rules to guide your practice.
As you keep improving, you recognize more and more rules even as the first ones you learned become intuitive and natural.
At some point, your intuitive model is rich enough that imposing additional rules on top of it decreases performance, and you should stop consciously applying rules and do what is natural.

You learn explicit rules to attain competence, and you learn to

break

from the rules’ constraints to attain mastery.

Going through the stages for any worthwhile skill takes many years. Most people who are skilled at writing or basketball or office politics started practicing as little kids. When they say they never had to learn explicit rules, it often means that they were taught the rules so long ago they forgot. They often give advice like “don’t think too hard” or “do what comes naturally” because it’s the last thing they had to learn. But it’s terrible advice for beginners who need to learn the first things first. The point of learning explicit rules is so that “what comes naturally” is something that doesn’t suck.

When I learned how to coach tennis I (re)learned at once dozens of guidelines to impart to my students. But when I actually coached kids I would only instruct a student on one rule like “follow through over your opposite shoulder” at a time until the student would do it reliably (and thus, intuitively). Applying rules explicitly relies on

type 2 thinking

and working memory, which can hold no more than one “tennis rule” at once.

Type 2 thinking is also slow and effortful. Striking a tennis ball while also concentrating on a sentence-long rule is harder at first than merely swinging at a ball, so students often seem to do worse when they start learning things explicitly. But eventually they get better. Skillful execution depends on fa...
Unfinished Projects Thread
by Gunnar_Zarncke — 2022-04-02T17:12:52.539Z

Post about your unfinished projects, incomplete inventions, or not-so-crazy ideas here.

This is an easy-entry version of the old Crazy Ideas Threads.

in the short run giving LessWrong members and lurkers a stronger incentive than usual to write well-received stuff has the potential to be great for the site.

I am posting this in the spirit of the Good Heath Week, especially as a place for lurkers to offer their thoughts and maybe grow them.

Please post one project/idea per thread.
What words should be shorter in the rational dictionary?
by brook — 2022-04-02T16:46:15.911Z

I read some linguistics books a while back, and more recently I've been reading (against my better judgement) Mad Investor Chaos and the Woman of Asmodeus. So, I've been thinking about word length and concept importance a lot.

Question 1: Should we be picking one or two syllable words for phrases/concepts central to thinking better? Is the hit to interpretability (which LessWrong is not really optimised for as is) worth it? What other significant costs am I missing?

Question 2: Which phrases/concepts?
[Invisible Networks] Psyche-Sort
by Kaj_Sotala — 2022-04-02T15:40:05.279Z

Written for crtlcreep’s Invisible Networks 2022 challenge: “invent a social network each day”, today’s prompt: “Psyche-Sort”.

Starting from day #2 since I forgot to participate yesterday.

Content note: Cycles of abuse, both personal and institutionalized. A world locked into AI-mediated dystopia.

“Tune your ear to the frequency of despair, and cross-reference by the longitude and latitude of a heart in agony.” (Amazing Spider-Man #544)

There are tendrils of pain running across society, fault lines on which our social infrastructure is built. You can imagine them as huge beating arteries full of thick flowing trauma, their contents seeping everywhere around them.

When you have lived your whole life in pain, it won’t occur to you that it would be possible to end the pain. You just enact and pass on the behaviors you’ve learned for dealing with it. And then you weaponize them, so as to prevent anyone else from hurting you more than you can hurt them.

Yet you cannot entirely eradicate the need for connection and companionship. You can suppress it, you can make it into something people are terrified of, you can turn it into a twisted mockery of itself. But people still long to band together, for mutual protection if nothing else.

So you require people whose needs have been twisted in a way that is compatible with yours. Maybe you believe that everyone is just out to hurt everyone else, and need your friends to treat you like trash so you can treat them like that in return. Maybe you are horrified at the thought of not being dependent on someone, so you need someone to tell you how you will always need them. Maybe you are utterly consumed by self-doubt, so need to follow a strong authoritarian leader. Maybe you feel unsafe by people around you exhibiting agency, so you need to become the strong authoritarian leader.

Either way, you need to be surrounded by people who tell you what you want to hear, treat you the way you want to be treated, and let you treat themselves the way you want to treat them.

Nobody intentionally created Psyche-Sort. It’s just an agglomeration of machine learning systems, each learning what kinds of people to connect with each other. Developed to match people on their revealed rather than stated preferences – the economists claiming that this is a far more reliable way of discovering what people really want, not to mention more profitable – it f...
Moloch and the sandpile catastrophe
by Eric Raymond — 2022-04-02T15:35:12.552Z

It often feels good to slide down efficiency gradients, but they can have tragedies at the bottom. Scott Alexander taught us to name this problem: he called it Moloch.

There is war in the Ukraine. The world's largest wheat exporter, Russia, is fighting the world's fourth-largest wheat exporter, Ukraine. Russia's ability to get paid for its exports is under threat; Ukraine's production has been so badly hammered that it will likely be a net wheat importer for years. As a result, there is a very strong near-term possibility that hundreds of millions of people in the Middle East, Africa, and Asia will starve. Even where starvation does not kill directly, political unrest and food wars may do it.

Understanding how we got here is important. Bear with me, I will get to a rationality heuristic, but there's a story to tell first.

Pre-industrial societies were chronically vulnerable to famine because all staple food production was local and could be disrupted locally. Elites might import spices from the Indies but transport costs and risks were too high to allow long-distance food dependency to develop. This only began to change in the 1700s with the mass importation of sugar, tea, and coffee to Europe. Even though these were luxury goods that could have been foregone, one of the consequences of the trade was the first global war - the Seven Years' War of 1756-1763.

The globalization of food production took its next major step in the mid-19th century when the developed world became dependent on phosphate fertilizers to perk up tired soils. Minor wars were fought over literal birdshit - guano islands were a critical phosphate source. But the phosphate flowed; none of those conflicts seriously disrupted it. The life-critical consequences of phosphate-supply disruption got consigned to the bin marked "That Will Never Happen".

Then came the post-1945 Pax Americana, with the U.S. Navy guaranteeing global free trade. National economies went into a frenzy of optimization by seeking comparative advantages. Places where food production was expensive outsourced it to places where it was cheap. A population boom followed. Peaceful, steady global trade became life-critical to a large fraction of humanity in a way it had never before been in all of history. And nobody noticed this!

Nobody noticed...
Moral Anti-Realism: Introduction & Summary
by Lukas_Gloor — 2022-04-02T14:29:01.751Z

I recently finished a

9-post sequence on moral anti-realism

over on the Effective Altruism Forum. This introduction explains my goals in writing the sequence and summarizes its main insights.

A little further down, I will comment on which posts are most worth reading for readers with particular interests since I expect many readers to be partially interested but unwilling to commit to reading the entire sequence.

Why I wrote this sequence

I had several goals in writing this sequence.

Laying out why moral anti-realism is likely correct
Building a framework for moral reasoning under moral anti-realism
Providing a shared basis for (meta)ethical discussion
Highlighting the implications for effective altruism

The first bullet point is self-explanatory, but I’ll say more about the second, third, and fourth bullet points.

Building a framework for moral reasoning under moral anti-realism

People build self-consistent philosophical frameworks to reason about the things they care about. Apparent shortcomings of a framework get patched as proponents find ways to accommodate them. For that reason, and because blindspots are generally hard to locate from within a given framework, I believe that the best way to change someone’s mind on realism vs. anti-realism is not by focusing on a single locus of disagreement, but by having people inhabit each others’ entire reasoning frameworks.

This is why, next to arguments against moral realism, I also outline how I would reason about morality as an anti-realist. Perhaps the strongest argument for moral anti-realism is that we can still reason about morality comprehensively and satisfyingly. If anything, I think figuring out moral reasoning under anti-realism is exciting. I found writing these parts of the sequence particularly interesting because it involved

conceptual engineering

, and the result feels like progress. Writing the posts forced me to think about moral reasoning in more detail than before.

Providing a shared basis for (meta)ethical discussion

Normative-ethical disagreements often spiral into metaethical disputes, which can be notoriously intractable when people seem to be using words differently or fail to understand each others’ concepts. I wrote this sequence hoping it could serve as a shared basis for discussion. When two people want to hash out their ethical or metaethical views, using this sequence (or select parts) ...
Retrospective: Practical Social Networking
by  — 2022-04-02T14:01:28.128Z
Link: https://guildoftherose.org/articles/retrospective-practical-social-networking?utm_source=lw&utm_campaign=retro-psn

Practical Social Networking was the third Guild of the ROSE course. Taught by Councilor David Youssef, the course was an introduction to the art of growing and nurturing a healthy social web. While some people got a lot out of it, we also struggled with engagement and there were some missed opportunities.
Optional stopping
by Ege Erdil — 2022-04-02T13:58:49.130Z

I offer you an opportunity to play the following game: if you agree to play, I will flip a fair coin until you tell me to stop, and for each toss of the coin if the coin comes up heads I'll pay you 1$, if the coin comes up tails you'll pay me 1$. Your advantage is that you can stop playing the game whenever you want. How much should you be willing to pay to play this game if you only care about the expected value of your payoff, i.e. if you have linear utility?

Let's try to work this out. If V is the expected value of the game for you, then V solves V=max{0,((V−1)+(V+1))/2}=max{0,V} because you can either stop for an expected value of 0 or toss a coin for an expected value of V−1 with probability 1/2 and V+1 with probability 1/2, and we assume you make the optimal choice.

Well, that got us nowhere: this equation is solved by any V≥0. All we learned is that the expected value of the game is not negative, which is trivial since you can always just choose to stop the moment you start playing! What's worse is that under our setup this Bellman equation seems to be the only constraint we can find on V, so it seems as if we should say this game has no well-defined expected value.

The bounded game

Let's investigate another variant of this problem to see what we can say about it. Suppose we both have finite bankrolls, A,B respectively for you and me. The game must stop when either of us hits zero, since then we're not guaranteed to be able to pay if we lose the next coin toss.

In this case, your expected value will be a function of both our bankrolls, and the Bellman equation will now become

V(A,B)=⎧⎨⎩max{0,(V(A+1,B−1)+V(A−1,B+1))/2}ifA,B≥1V(A,0)=0V(0,B)=0

Now we can prove that there is only one solution and that is V=0 everywhere. Clearly V≥0 everywhere by definition, so we can remove the maximum and simply solve the equation

V(A,B)=⎧⎨⎩(V(A+1,B−1)+V(A−1,B+1))/2ifA,B≥1V(A,0)=0V(0,B)=0

The nice thing about this is that it is a decoupled set of single-variable functional equations on each line A+B=N for all N, and on each such line the function must be zero because it's harmonic with zero boundary conditions on both ends. To make this explicit, suppose we fix N≥1 and define c=V(1,N−1). Then, we'll have

2c=2V(1,N−1)=V(2,N−2)+V(0,N)=V(2,N−2)

4c=2V(2,N−2)=V(1,N−1)+V(3,N−3)=c+V(3,N−3),V(3,N−3)=3c

and from here it's easy to show by induction that V(k,N−k)=kc. However, we also know th...