lambdaphage

I don't remember-- it must have been either differential geometry or topology, but I think the theorem in question was the inscribed angle theorem: http://www.proofwiki.org/wiki/Inscribed_Angle_Theorem. Not a difficult theorem, but you had to know it well to be able to see the application immediately.

I don't know-- usually the answer to such questions about academic priorities is "because it was cheaper", but they just seemed to emphasize geometry much more at the K-12 level. It's a generalization, of course, but a pretty robust one. One of my professors came from Kazakhstan, and once casually remarked that a certain problem on a homework set was "impossible unless you were Russian", since the proof was easy if you knew a certain proposition from Euclid, but extremely tedious without it.

EDIT: this interview with Izaac Wirzsup comparing the Soviet and US systems confirms my prejudice:

  Another extremely harmful feature
  of [the US] school mathematics programs
  is that only about half of our students
  take geometry, and for only one
  year, generally in a concentrated high
  school course. Students cannot be
  expected to master the material taught
  in this way. Moreover, they are not
  being taught solid geometry, and they
  rarely have a workable perception of
  three-dimensional space, which is so
  essential for studying science,
  technical drawing, or engineering.
  Soviet children study geometry
  extensively for ten years, including
  two years of solid geometry.

I'm always surprised when reading the notes of scientists and mathematicians working in previous centuries to see just how steeped they were in synthetic geometry. This was taken to an extreme in the case of the Principia, but one can't read Gibbs or Maxwell either without realizing that they felt Euclid in their bones in a way that few people do today, with possible exceptions for mathematicians trained under the Soviet system.

What does "the impulse towards genetic determinism" mean here? Comparisons of identical twins raised apart show that physical appearance is highly heritable, so it would seem that "the impulse towards genetic determinism" is in this case correct.

> it's considered a settled issue that everyone is equally likely to get HIV.

I have no idea what this is supposed to mean. Under every interpretation I can think of, it is incorrect. In the first place, people vary in their CD4 and CCR5 (&c.) receptors, so they also vary in their susceptibility to HIV infection given exposure. My understanding is that some alleles confer such resistance to infection that carriers are considered naturally immune. As ever in immunology, that's not the entire story, but it certainly enough to falsify the view that "everyone is equally likely to get HIV" _even given exposure_.

More importantly, people have different rates of exposure. Those rates depend on what sort of potential transmission events one faces, and the prevalence of infection among partners for potential transmission events. Both of those differ between groups of people.

Hence, not everyone is equally likely to get HIV. That implies nothing, of course, about what we ought to _do_ about that.

> glibertarian

hmm.

It is a dreadful poesy to think that the last stargazer from this planet might have been a robotic rocket, looking up once at the fixed stars for all of humanity before ending it.

Adult lactose tolerance is the mutant phenotype-- intolerance is the norm.

Nice. I once needed to do reciprocal blast for the complete genomes of about 300 bacterial species. That's on the order of half a billion queries, but the work was embarrassingly parallel, and each discrete job only took about 90 seconds. I wrote a little shell script to kick them off on the cluster, and went home.

I woke up the next morning to several inbox screens' worth of messages from angry people I didn't know, demanding explanations for what I did to their jobs and their cluster. I don't think I have ever biked to the lab faster.

After multiple rounds of palm-drenching emails with the cluster sysadmins and the computational mathematics group PI (and my own boss agonizingly cc'ed), we determined the cause. The cluster sysadmins, lacking imagination for the destructive naivete of their users, had not foreseen that anyone would want to submit more than 10^4 jobs at once. That broke the scheduler, preventing other people from running jobs and me from canceling them. Meanwhile the blast jobs blew past the disk quota, leading to a Hellerian impasse where I somehow lacked the space to delete files so I could create space. I still don't fully understand it.

I believe it took a full day to get the cluster back online.

I anticipate this reply here: https://news.ycombinator.com/item?id=7088378

Well, that really depends on what you consider a price: if a law prevents a landlord from renting to the tenant offering them the most money, they have to decide on the basis of some other criterion. In SF, you apparently had people showing up to open houses offering to pay the (legally stipulated) rent a year in advance. (http://www.lrb.co.uk/v35/n03/rebecca-solnit/diary NB: the author is apparently sympathetic to rent control) Moving a year's worth of future rent up to the present costs money in the form of interest rates, and is a cost. Landlords in rent-controlled units are notorious for dragging their feet on repairs, since the tenant is unlikely to look elsewhere and even if so, another occupant will always be ready to take over the lease. Just searching for a place in a rent-controlled district takes more time. All of these are costs, arising from the fundamental fact that if you make it illegal to allocate a resource on the basis of price, you still have to allocate it some other way.

You shouldn't be worried about rent control failing to function as a price ceiling-- you should be worried about it functioning exactly as a price ceiling.

I appreciate this link. I read it through, but I'm afraid it doesn't really present much of a case for... whatever it is Solnit wants to do about housing policy in SF, besides sneer at tech workers. I found the piece frustratingly long on vague innuendo and ressentiment, and short on arguments about what we ought to value, and how we ought to achieve it.

Many of her arguments, such as they are, seem to follow backwards from the desired conclusion that tech workers are awful and their employers, even worse. For example, consider:

> The Google Bus means so many things. It means that the minions of the non-petroleum company most bent on world domination can live in San Francisco but work in Silicon Valley without going through a hair-raising commute by car ... the corporations of Silicon Valley aren’t much interested in improving public transport, and in fact the many corporations providing private transport are undermining the financial basis for the commuter train.

Of course, if the companies didn't organize shuttle buses, then they'd be accused of ruining the environment by letting their employees drive nine hours every day. "How come the most powerful corporations in the world can't shell out for a shuttle bus", you can just imagine the author asking. Furthermore, suppose Google et al. did lobby California for a fifty mile commuter rail project from SF to SV that serves practically no one but... Google et al.'s employees. Headline: Greedy Corporations Buy Off Transit Authority for Tech Nerd Express, Shift Costs to Public. In general, I'm a big fan of public transit because I think it's a situation where collective action can often improve efficiency. But arguing that Google is destroying civil society by not 'heightening the contradictions' in order to get the transit authority to build a railway to nowhere is kind of rich.

Solnit's discussion of rent control is also pretty amazing. She punctuates her (completely understandable) complaints about the rental market with astonishment that the textbook unintended consequences of rent control persist despite rent control, never considering that they might be due to rent control. Prospective tenants supplicating to landlords, live-in couples occupying two units just to lock in tenancy, landlords dis-preferring long-term tenants, the overall lack of response in the housing supply to demand; these are classic symptoms which noted conservative Paul Krugman diagnoses in the article I linked elsewhere in this thread. If someone wants to write a piece in LRB defending rent control in SF, I'd sincerely like to read it. But you have to argue for it, not simply assume the desirability of a policy which is practically unanimously opposed by the people who study it professionally.

Finally, although I'm of mixed mind about whether I even want to indulge this line of thought, I find it pretty stunning that someone with Solnit's pedigree (http://en.wikipedia.org/wiki/Rebecca_Solnit#Early_life_and_e...) presumes to speak for the poor and downtrodden, those "more frail", in a first-person piece called "Diary". It's the same sort of tenor you find on flyers like this one (http://25.media.tumblr.com/3fd37355541474385f8db330e58ebb0f/...). The author, who fancies themselves immersed in "poverty, homelessness and death..violence and degradation", makes it painfully obvious that they have at least one liberal arts degree.

From what I've read so far, it seems to me like the "opponents"* of tech workers in the bay area are basically the cultural ancien regime, upset about losing their cool digs and relative status to a bunch of nerds (Solnit is pretty explicit about this). If that's what this is about, I wish they'd just say it. And if they're genuinely concerned about the legitimately poor,* they should recommend serious proposals, and would probably have the support of many of the "technocrats" Solnit so despises. But mixing and matching leaves me short on both pathos and policy.

---

* I use scare quotes because I still don't understand what they want to do about tech workers in SF, except disdain them so hard. Which, have at it...

* * A group that, by the way, has practically zero intersection with the set of people to whom it would occur to hand out passive-aggressive, Flesch-Kincaided-out typeset essays concluding with "GET THE FUCK OUT OF OAKLAND"

* * * I also suspect I am less outraged than Solnit is that a man cannot make a living as the almost-Poet-Laureate of San Francisco, and must find a cheaper place. I'm not making this up.

Sure, and the question is how you achieve those aims. If you can read an op-ed by one of the most highly respected progressive economists in the world, whose message is:

> Rent control in SF has had perverse consequences for tenants. Don't go in for rent control.

and your conclusion is

> Maybe we should go in for rent control.

I'm not sure what else to say.

What criterion do you suggest to determine who lives in SF, besides "let people come to mutually beneficial arrangements among themselves"? Keep in mind that the most common alternative policy, rent control, is widely acknowledged (http://www.nytimes.com/2000/06/07/opinion/reckonings-a-rent-...) to turn rental markets into basket cases.

There are currently a host of policies that keep people from doing what they would otherwise very much like to do, which is building new higher-density housing and living in it. That would result in net gains, whereas arguing about who gets to live in SF is pretty much zero-sum. Yet people really seem to like to argue over the latter, and are weirdly quiet about the former.

If you believe an argument to be unsound, you can point out the error. That is one of many advantages arguments have over rhetorical questions.

Not to mention the 70% of Silicon Valley workers in the linked study (http://www.sfbg.com/politics/2014/01/15/study-30-percent-tec...) [note: figure comes from self-reports] who would stay and presumably commute by car.

I'm pretty confused about how shuttle buses became the preferred metonymy for corporate evil. As if replacing each bus with twenty cars would make SF a better place for anyone?

I've read your comments three times, and the original article twice. I'm still very confused about what your point is.

Before I read your comments, which call direct attention to the author's style, my impression of it was that the author was writing in a deliberately informal, encouraging and sympathetic tone. The material is somewhat difficult, he admits, but not as difficult as it is made out to be, and the reader will be rewarded with the understanding of an elegant concept if they just push on for a bit. Having read and done a bit of mathematics myself, I recognize this tone as the one I try to adopt when I explain concepts to others, or write notes for my own understanding. (Which is half of the reason Kun writes these things himself, I assume. Kudos to him for it.) It is far from condescension-- if anything, it is _commiseration_.

Your concerns, so far as one can find them stated explicitly, are nits about style. These would be minor even if they were accurate, but they are not. For example, "half in jest" is twice as popular as "half-joking", according to google. "We", as other commenters have noted, would have been perfectly fine even if it weren't alraedy completely standard usage in mathematics. Which it is. I am reminded of a line from the "Note on Notation" in Hodges' _Model Theory_:

> 'I' means I, 'we' means we.

For all the objections about uncommon vocabulary, I can't help but observe that the only usage that seems to have confused readers in this thread (myself included) was "tofferies". But I learned a new word today, so thank you for that.

But I still don't understand how "jest" is "symptomatic of a particular discourse that makes assertions regarding social order and fundamental power relationships between humans". In fact, the phrase:

> symptomatic of a particular discourse that makes assertions regarding social order and fundamental power relationships between humans

strikes me as _rather a lot more_ "symptomatic of a particular discourse that makes assertions regarding social order and fundamental power relationships between humans". In particular, the discourse of critical theory, which has become so cloistered and self-referential that you can pick it out a mile away. I would be grateful if you would spell out exactly what those assertions are, so long as you are charging the author with making them.

I catch another whiff of that with phrases like "he is bluntly interpolating an elite". Either you mean "interpolating" in the sense of approximating a function between two known values, in which case I have no idea what you're talking about. Or you mean "interpellating", in the Althusserian sense, which is the only interpretation that the context seems to support. But in that case, look what you're doing: you're walking into a forum on hacking with highly, _highly_ abstruse jargon that even the average English-speaking philosopher does not understand. I would say that you are hoist by your own petard here, but perhaps that phrase would strike you as oppressive.

Finally, I don't understand what you intend by "an anxious situation". Do you simply mean that math produces anxiety? There's no shame in admitting that, but you might at least acknowledge that it's precisely that anxiety which Kun attempts to combat in his tutorial. I don't see how you can miss that Kun is, in fact, making an extremely generous effort to encourage the reader.

PS: Those "little tests of the intellect" are what we in math call "exercises", which are how one actually grasps the material. You cannot learn math by passive absorbtion-- you have to sharpen your pencil and puzzle it out for yourself. Not because "we did it so you have to, too", but because we sincerely know of no other way to put mathematical understanding in another human being's head. Well-selected exercises are actually a strong signal to the reader that the author really cares about the reader's comprehension.

I don't know of a charitable way of putting this, but for one criticizing the OP's engagement with the conventions of mathematical writing, you seem rather innocent of them yourself.

What.

Well actually, speak of the devil, I moved out of my last apartment specifically because my downstairs neighbors, who had lived there for years, were completely intolerable. If I could have waved a magic wand and replaced them with an AirBnB crash pad, I would have done so in an instant. Restrictions on short-term rentals are of little comfort when your long-term neighbors are worse. Then again, the arguments against short-term rentals go through just about as well for long-term rentals, so why not just restrict rental properties altogether? Many homeowners seek to avoid neighborhoods with high rental density, so why not make their jobs easier with a law?

As I said, there are plenty of attributes that make different houses more or less desirable to different people. If the OP had converted their apartment into a sarin gas factory or a practice pad for MBV, it might be a little more understandable why regulation would be efficient. As it stands, having a short-term rental next door strikes me as an extremely vague sort of source of disutility: all you can say with certainty is that you won't have long-term neighbors. Which many people are fine with in the first place. If people have varying preferences about living next to short-term rentals (either because they view them as a source of variety in se or just don't mind that much either way, as I do) then it should be more efficient to let people figure it out for themselves. People already self-assort into spatially resolved communities according to many other attributes (e.g. school quality, proximity to nightlife, population density; all attributes which reasonable people can value differently) so it seems strange to pick 'proximity to a short-term rental' as the one intangible neighborhood-character issue to treat like 'proximity to a meth lab'.

So let me just state again: I wouldn't mind living next to a short-term rental. In fact, if they're as widely despised as you suggest, I'd mind it even less because the housing market would be effectively subsidizing my tolerance.

People have lots of preferences about housing, which is why people tend to make an effort to suss out their housing options. Whether your neighbors are permanent or transient is just another dimension along which your preferences can vary. I don't understand why that preference in particular should be legally codified, whereas practically every other variable gets determined by people voting with their feet and dollars.

The same argument, after all, goes through for long-term renters too, whom a lot of people don't want to live next to. Should we zone all annual leases as well?

Our attitude towards any law really should be a presumption of doubt, especially laws that interfere with consensual activities. Laws are blunt objects that come with their own enforcement costs and unintended consequences. We should be especially wary about regulations whose benefits are sharply concentrated among a small group (say, hotel owners), and whose drawbacks (say, slightly higher hotel costs for everyone else) are widely dispersed. That's standard public choice theory. That doesn't mean that no regulations are ever justifiable (far from it!), but it does suggest that we not favor regulation for the sake of regulation.

I don't like to psychologize people, but I wonder whether this attitude is a sort of mental heuristic on the left, which often finds itself fighting with folks on the right who seem to believe, roughly, that regulation is intrinsically bad, and should be abolished. This has encouraged the counter-formation of the view that regulation is intrinsically good, and should be preserved. I guess that's a little easier to remember than the subtler view that regulation is intrinsically bad, but should sometimes be preserved when it can still improve outcomes over the status quo.

It's almost as though you have to examine things case by case and decide whether a dangerous tool should be applied, instead of just forming a mental affiliation with it.

If you keep treating your intellectual opponents like this, you're going to get trounced the next time you run into a smart one.

To be very brief, you seem to think that libertarians believe, roughly,

(1) "the world is simple, so we should have simple rules."

Instead, you suggest:

(2) "the world is complicated, so we should have complicated rules."

But this claim is entirely unresponsive to:

(3) "the world is complicated, so we should have simple rules."

which is what most libertarians I know actually think. If you respond to (1) when your opponents are arguing for (3), you will not have productive conversations.

Just to lay my cards on the table: I'm registered as a member of the US Green Party and have been involved with various left wing activist movements since I was fifteen. I've also been poor, living in a junkie hotel and doing day labor for cash. My most upvoted comment on hn (before I ragequit my previous account (for basically leftist grievances (!))) was one describing what that was like.

Still, I find the intellectual attitude that you've described deeply unsettling. As you've sketched it, the "social justice narrative[0]" is unfalsifiable: what claims does your theory of politics actually make about the world if any given piece of it can be overturned without making a dent in the theory itself? A theory of social inequality can't be correct in general without being correct in particular cases. Refuting (not "deconstructing") a particular thesis is not "intellectual showboating", it's engaging in argument. What else is someone who sincerely disagrees with you supposed to do?

I've seen this happen with depressing regularity: a self-styled social justice advocate will make a claim, and sometimes that claim will get demolished by an intelligent opponent. (Yes, this can happen, and it is a portent for the future of the left that most activists never learn to take a drubbing from a perceptive conservative.) Rather than taking stock at that point, the social justice advocate throws up a polysyllabic ink cloud ("institutional", "systemic" and "societal" seem to enjoy heavy rotation) and jets away. Whether it is true or not that nebulous social forces conspire to constrain outcomes for the poor in the way that the social justice advocate believes, I have no idea why such verbal behavior should be considered convincing.

This is especially frustrating if you actually sincerely think that the left has good ideas about social policy that should be argued for in earnest and implemented.

---

[0] The heavy rhetorical weight placed on the word "narrative" also gives me goosebumps. What happened to plain old arguments-- a set of propositions intended to establish (or at least raise the probability of) the truth of a conclusion? I would hate to think it's because "narratives", unlike arguments, are impossible to demonstrate or refute.

Mathematical biologist here. There are lots of criticisms of the state of mathematical competence in biology I could offer, but power analysis really isn't one of them-- that is typically the one thing that _is_ taught well, if only because data collection can be so difficult. That is not to say that no clinical trials have ever suffered from badly handled statistics, but the issues are usually subtler than "we forgot to determine how many observations we'd need to detect an effect."

Sorry, I should have clarified-- my boss is Spanish but works in computational biology, not Spanish lang/lit.

That's a general problem with the interpretation of test answers. What an appropriately penalized scoring scheme for a multiple choice tests does is set the expected value of guessing to zero, providing an unbiased estimator of performance for students who guess randomly.

My graduate advisor is Spanish, but is faculty at a university in the States. In his first year of teaching, he penalized for incorrect answers (as is apparently the Spanish custom). But his students threw fits during office hours, so he caved in the face of potentially terrible teaching evaluations.

After tenure, he said, things will be going right back to the way they were in the old country.

I don't understand why it even requires more effort. Here's one of the emails Sharp cites:

  <mchehab@redhat.com> wrote:
  >
  > Are you saying that pulseaudio is entering on some weird loop if the
  > returned value is not -EINVAL? That seems a bug at pulseaudio.
  
  Mauro, SHUT THE FUCK UP!
  
  It's a bug alright - in the kernel. How long have you been a
  maintainer? And you *still* haven't learnt the first rule of kernel
  maintenance?
  
  If a change results in user programs breaking, it's a bug in the
  kernel. We never EVER blame the user programs. How hard can this be to
  understand?
  
  To make matters worse, commit f0ed2ce840b3 is clearly total and utter
  CRAP even if it didn't break applications. ENOENT is not a valid error
  return from an ioctl. Never has been, never will be. ENOENT means "No
  such file and directory", and is for path operations. ioctl's are done
  on files that have already been opened, there's no way in hell that
  ENOENT would ever be valid.
  
  > So, on a first glance, this doesn't sound like a regression,
  > but, instead, it looks tha pulseaudio/tumbleweed has some serious
  > bugs and/or regressions.
  
  Shut up, Mauro. And I don't _ever_ want to hear that kind of obvious
  garbage and idiocy from a kernel maintainer again. Seriously.
  
  I'd wait for Rafael's patch to go through you, but I have another
  error report in my mailbox of all KDE media applications being broken
  by v3.8-rc1, and I bet it's the same kernel bug. And you've shown
  yourself to not be competent in this issue, so I'll apply it directly
  and immediately myself.
  
  WE DO NOT BREAK USERSPACE!
  
  Seriously. How hard is this rule to understand? We particularly don't
  break user space with TOTAL CRAP. I'm angry, because your whole email
  was so _horribly_ wrong, and the patch that broke things was so
  obviously crap. The whole patch is incredibly broken shit. It adds an
  insane error code (ENOENT), and then because it's so insane, it adds a
  few places to fix it up ("ret == -ENOENT ? -EINVAL : ret").
  
  The fact that you then try to make *excuses* for breaking user space,
  and blaming some external program that *used* to work, is just
  shameful. It's not how we work.
  
  Fix your f*cking "compliance tool", because it is obviously broken.
  And fix your approach to kernel programming.
  
                 Linus

329 words. Here is the same email with the dramatic noise removed, and patched up for clarity when necessary:

  <mchehab@redhat.com> wrote:
  >
  > Are you saying that pulseaudio is entering on some weird loop if the
  > returned value is not -EINVAL? That seems a bug at pulseaudio.
  
  It's a bug alright - in the kernel.
  
  If a change results in user programs breaking, it's a bug in the
  kernel. We never EVER blame the user programs. 
  
  To make matters worse, commit f0ed2ce840b3 is [broken] even
  if it didn't break applications. ENOENT is not a valid error
  return from an ioctl. Never has been, never will be. ENOENT
  means "No such file and directory", and is for path
  operations. ioctl's are done on files that have already been
  opened, there's no way in hell that ENOENT would ever be valid.
  
  > So, on a first glance, this doesn't sound like a regression,
  > but, instead, it looks tha pulseaudio/tumbleweed has some serious
  > bugs and/or regressions.
  
  [This is wrong.]
  
  I'd wait for Rafael's patch to go through you, but I have another
  error report in my mailbox of all KDE media applications being
  broken by v3.8-rc1, and I bet it's the same kernel bug. [Your
  patch doesn't work] so I'll apply it directly and immediately
  myself.
  
  WE DO NOT BREAK USERSPACE!
  
  The whole patch is broken. It adds an incorrect error
  code (ENOENT), and then because it's wrong, it adds a few places
  to fix it up ("ret == -ENOENT ? -EINVAL : ret").
  
  Breaking user space, and blaming some external program that
  *used* to work, is wrong. It's not how we work.
  
  Fix your "compliance tool", because it is obviously broken.
  
                 Linus 

209 words: a savings of more than 33%.

Crick was perhaps halfway into a Ph.D. in physics when the war broke out, during which he basically did very applied physics for the British. After the war, he did a Ph.D. under Max Perutz on X-ray diffraction. Crystallography is very useful in biology, but it is itself very far from a biological topic. Crick wrote of experiencing extreme impedance mismatch when he switched from physics to biology and, perhaps most significantly, Watson often referred to Crick as 'the physicist' or to 'having him do the physics' (sorry, I don't have the full text in front of me) in The Double Helix, suggesting that his approach to biological problems was primarily a physical one. It is true that Crick did work under the Medical Research Council, but it is somewhat misleading to say that he was doing medical research in the conventional sense. He was studying the biophysics of cytoplasm, which is not something that people trained in medicine do.

I admit that Hodgkin and Huxley are harder cases: both had early inclinations to physics and then got sidetracked into physiology. Both of them spent the war doing things you'd have a physicist doing during a war, and afterwards did their their famous work on the action potential. I read the Hodgkin and Huxley papers, but I read them in a course in the math department-- they contain some of history's finest examples of mathematical modeling, relying heavily on dynamical systems and circuit theory. It is a regrettably rare biologist who wants to go near those papers. It is manifestly not the work of traditionally trained biologists.

Disciplinary boundaries in mid-century Britain were somewhat different then, and I realize the danger of playing No True Biologist. But the mainstream of biology is only very recently acknowledging the importance of the physical approach: Hodgkin and Huxley could have been Hodgkin and Huxley without a lick of genetics or ethology, but they couldn't have been Hodgkin and Huxley without the cable equation.