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marchenko

1,349 karma · joined October 12, 2015

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marchenko··on Leonard Euler's Solution to the Konigsberg Bridge Problem (2006)
Would traveling to the source of the river Pregel and walking around it count as a solution?
marchenko··on Google's censored Chinese search engine: a catalogue of ethical violations?
This is a good point. What value is Google search in China adding beyond better-targeted and more profitable ads - a filter bubble within a filter bubble? Will Google Books be available? Is Project Gutenberg available in China?
marchenko··on Discovery of nitrogen-fixing corn variety could reduce need for added fertilizer
Thanks for the link to the paper. This is potentially very exciting news - the benefits of Three Sisters agriculture with one of our staple crops.
marchenko··on Consumer DNA tests revealing misattributed parentage
>> "why was she wearing that dress?", "why was she in the club on her own if she was in a relationship?", "why did she walk through the park at night on her own?"

>What? This is simply a lie. You know it.

This statement is highly uncharitable to your interlocutor above and frankly ignorant of the history of sexual assault prosecutions in the US. There has been a longstanding and documented strategy of defense attorneys trying to paint the alleged victim unsympathetically to try to elicit a just world theory-based response: "she was engaged in dangerous behaviour - that couldn't happen to someone like me".

It is important to distinguish the high-profile Title 9/social media kangaroo courts with the workings of the actual US justice system.

marchenko··on Consumer DNA tests revealing misattributed parentage
The actual rate of non-paternity in western societies is closer to 3%. The 10-20% figures that appear regularly on the internet are largely derived from rates of non-paternity in cases were paternity was questioned (i.e. pre-existing suspicions of infidelity). The higher ranges quoted (30% is the highest I have seen) are generally from small study populations with extended periods of partner absence, like central American itinerant laborers or African truck drivers.
marchenko··on Ask HN: Favorite note-taking software?
This is excellent news for anyone nervous about vendor lock-in, which is a big problem in the notes space.
marchenko··on Ask HN: Favorite note-taking software?
I appreciate your excellent work. Google Keep, for example, exports both a .json and a folder of individual html files. I ended up piping the individual .html files through pandoc to .md files for idiosyncratic reasons. To be fair, I think turtl is so many leagues ahead of other solutions on the rest of its feature set that a .json export - which appears to be standard - is enough.

I suspect that turtl appeals to a lot of users with a large directory of plaintext notes who would be enticed to adopt the service if bulk textfile import were also streamlined. I hope the next release is a success!

marchenko··on Ask HN: Favorite note-taking software?
Possibly answering my own question, I just discovered tagspaces (https://www.tagspaces.org/) for tagging files across a filesystem.
marchenko··on Ask HN: Favorite note-taking software?
I love Turtl's interface, tagging system, hosting options, multi-OS setup, and privacy stance. Turtl would be my go-to solution if they supported .md import/export. I think they have .json export planned for the next release, which might be tractable with a bit of pandoc manipulation, but not ideal.
marchenko··on Ask HN: Favorite note-taking software?
I use Jotterpad on Android to edit markdown and text files. It syncs well with Dropbox (it feels just like a frontend for a dropbox folder) and supports .txt, .md, .markdown, and .fountain files.

I use Brackets and Typora to edit .md files on pc/mac/linux. I find image handling in .md files fairly simple as long as you maintain an appropriate folder structure on the backend. Typora makes this especially easy.

I would like to build a better self-hosted tagging/viewing program for my huge cache of notes - something like Google Keep without being, well, Google. Turtl comes closest to my needs, but the lack of import/export at this point is a problem. I do not wish to be tied to a particular format or storage space.

marchenko··on What makes a country good at football?
I think interest in women's soccer in the US is much more organic than this comment implies. Soccer was touted to young girls (and their parents) in the 90s and 00s as a safe and inexpensive sport particularly well-suited to women; one of the few where women can play with pretty much the same rules and equipment as men (contra softball, basketball, football). And it had a bit of foreign mystique. So there is a fairly large spectator pool of women familiar with the sport from high school or club sports who follow the games, as do some of their siblings and parents. Men are more interested in the sports they played as kids. University-level athletes are such a small population that they don't really affect viewership much. I don't even think Title 9 accommodations have much to do with the female talent pool; as in most of the world, US soccer players get hooked early and start intensive training before University. They just happen to be predominantly female.
marchenko··on Analysis: How poverty can drive down intelligence
I think the term is meant to draw attention to the fact that most study populations in psychology meet all of these criteria (a disproportionate number are college students, for example) and are statistically unrepresentative of the majority of humanity. Therefore their responses should be interpreted/extrapolated with caution - they are demographically "weird". It's not really intended to cast aspersions on the people themselves.
marchenko··on Theology majors marry each other a lot, but business majors don’t
I wonder if there is a degree of separation from other students influencing the homogamy here: theology is often taught in a separate school of Divinity (eg Harvard), and at least some large universities have separate schools of Agriculture and Architecture ( eg Cornell).
marchenko··on Relative's DNA from genealogy websites cracked East Area Rapist case
This 'bias' is not necessarily inappropriate because of the inherent asymmetries of DNA evidence - it is statistically more powerful for exoneration than conviction. This is because of the False Positive Problem (similar to the Birthday Problem in probability): if the actual incidence of a phenomenon is lower than the false positive rate of the test, a positive result is likely erroneous even on a highly accurate test.

This is why a strong prior, developed through traditional policework, is necessary to increase the reliability of DNA results - most results obtained through database trawling will be false - and these will be numerous if the database is large enough. It is also part of the reason why exonerations are more robust than identifications.

This particular case may not suffer from these statistical problems, but they are worth keeping in mind, as it sets a precedent.

marchenko··on Put Down the Pitchforks; Amazon Didn't Steal Your Dunning-Krugerrands
Did this author "coin" the term Dunning-Krugerrand? Because it's brilliant.
marchenko··on [dead]
Well, I just hope those "aggressive, impulsive" large-breasted women aren't buying plate armor with a chest divot before they go on their raids, or they're going to have a bad time.

I wonder if the 2 physiology studies noted in the review are at all influenced by the fact that they were carried out in populations of ~100 college students before Return of the Jedi was initially released?

marchenko··on Police chief said Uber victim “came from the shadows” – don’t believe it
I'm not trying to be inflammatory, but should we expect the Tempe AZ City administration to be a neutral source of information in this case? Might they be biased by their decision to host this experiment in their jurisdiction (in the sense of anticipating criticism)?
marchenko··on 23andMe Granted FDA Authorization for Genetic Test on Cancer Risk
Additionally, many harmful mutations are essentially "private" within a family and do not inform any of the GWASs used to create these SNAP chips. Regional sequencing is still important for persons with a family history of illness.
marchenko··on Women who clean at home or work face increased lung function decline
I wonder if there is a similar effect observed in people who cook regularly - especially at high temps or in poorly ventilated spaces. Cleaning the exterior and filters of the exhaust cabinet makes me wonder about the interiors, of, for instance, apartment dwellers doing wok frying.
marchenko··on Demographic Consequences of Defeating Aging
The Book Algorithms to Live By describes some research which found that it is not chronological age, but rather one's position on the explore/exploit curve that drives the apparent conservatism of old age. So a 70 year old who expects to live 50 more years might be considerably more novelty-seeking than a 70 year old who expects to live 20 more years, because the first has a longer interval within which to exploit the benefits of any useful finds.
marchenko··on My new favorite book of all time
In particular you see that there is NO country today which is as badly off as EVERY country was 200 years ago.

I tend to believe that this argument is generally true, but some researchers have argued that it is very sensitive to the specific endpoints chosen. In his preface to A Farewell to Arms, economist Greg Clark argues (about the world circa 2007):

> "Prosperity, however, has not come to all societies. Material consumption in some countries, mainly in sub-Saharan Africa, is now well below the preindustrial norm. Countries such as Malawi or Tanzania would be better off in material terms had they never had contact with the industrialized world and instead continued in their preindustrial state. Modern medicine, airplanes, gasoline, computers—the whole technological cornucopia of the past two hundred years—have succeeded there in producing among the lowest material living standards ever experienced. These African societies have remained trapped in the Malthusian era, where technological advances merely produce more people and living standards are driven down to subsistence. But modern medicine has reduced the material minimum required for subsistence to a level far below that of the Stone Age."

Clark also argues that:

>"Indeed in 1800 the bulk of the world’s population was poorer than their remote ancestors. The lucky denizens of wealthy societies such as eighteenth-century England or the Netherlands managed a material lifestyle equivalent to that of the Stone Age. But the vast swath of humanity in East and South Asia, particularly in China and Japan, eked out a living under conditions probably significantly poorer than those of cavemen. The quality of life also failed to improve on any other observable dimension. Life expectancy was no higher in 1800 than for hunter-gatherers: thirty to thirty-five years. Stature, a measure both of the quality of diet and of children’s exposure to disease, was higher in the Stone Age than in 1800. And while foragers satisfy their material wants with small amounts of work, the modest comforts of the English in 1800 were purchased only through a life of unrelenting drudgery. Nor did the variety of material consumption improve. The average forager had a diet, and a work life, much more varied than the typical English worker of 1800, even though the English table by then included such exotics as tea, pepper, and sugar"

A lot of present arguments seem to center on the shape and AUC of the progress curve, and whether that has any implications for predictions based on historical data.

marchenko··on My new favorite book of all time
Pinker has been repeatedly criticized for his focus on combat deaths, and with good reason. The technological advances of war have shifted the balance of casualties from combatants to civilians, and increased the fat-tail risk of escalating conflicts. This is another iteration of the same.

This is my main reservation about the Better Angels thesis: we may be replacing regular threats of (relatively)limited scope with existential threats. It seems like we are building a complex ratchet mechanism made up of entangled components. Many of these threats don't actually disappear, but are held in abeyance by continual technological progress, resource substitution, or our own fears of upsetting the ratchet.

I think Pinkerian thought is strong when it argues that we are currently in a much better time than, say, the Plagues of Justinian, where war, disease, and famine affected a huge part of the western hemisphere. But I wonder if our present condition is more fragile than our large population and social/technological advancement would lead us to believe.

marchenko··on China, Unhampered by Rules, Races Ahead in Gene-Editing Trials
Some of the problems with dog breeding are due to the inefficiency of he breeding process, but others are simply the direct biomechanical consequences of the desired traits; for example the neotenous compressed faces of many lapdog breeds have consequences for mastication, respiration, and orbit shape that can't really be addressed without relaxing our selection for that particular look or accepting other tradeoffs.
marchenko··on Experiments reveal faculty preference for women on STEM tenure track (2014)
The simulation of an academic job search used in this study is not very much like a real academic job search. This study was well designed, but it is harder to do a faithful blind replication of the hiring process in academia vs the public or private sector because job searches are much rarer, and most of the applicants are known - at least by reputation - by most of the evaluation committee - their future coworkers.

The researchers made a strong effort to obscure the goal of the study, but if you are an academic participating in an artificial candidate search, you are likely to suspect that one of the variables being tested is either sex, race, or both. The experiment where evaluators rated a single candidate addresses this somewhat, but even in that case the participants are almost certain to have known that there was no job search in progress, and very likely to have realized that there was a socially desirable response possible to be given at no cost. By no cost, I mean that this person is not going to show up and take space and resources that could go to your preferred candidate/collaborator.

marchenko··on DNA Testing Botched My Family's Heritage
Surreptitious DNA collection requires some level of targeted effort: someone must have a prior interest in you specifically, which is unlikely for most persons. Uploading your DNA to a database exposes you (and your relatives) to all sorts of Birthday-Problem-like mischief from persons and organizations trawling the database.

The best defense to the current threat landscape (privacy violations related to insurance, employment, and the law) is to define your genome-related queries as narrowly as possible and type/sequence only those relevant loci/regions.

marchenko··on India has a hole where its middle class should be
The term 'Food desert' was used primarily to refer to total healthy food availability within a certain radius, including (especially) healthy food availability in supermarkets.

Yodsanklai appears to have been referring to the availability of healthy prepared foods, particularly restaurant foods. It is entirely possible to live in an area well-served with supermarkets and bodegas and only have 'unhealthy' restaurants to choose from due to the peculiar demands of that area. You can drive through parts of the US and see nothing but greasy spoons or pub food, while the local at-home cooks have access to a wider variety of healthy foods from the markets.

marchenko··on Juicero Founder Now Promoting $40 Jugs of ‘Raw Water’ in Silicon Valley
I've got several antique sealed glass carafes decanted from the Broad Street pump circa 1854... as an added bonus, I'll throw in the original lead stoppers.
marchenko··on How Neglecting Minorities in Medical Research Has Led to Deadly Outcomes
>Remove any notions of race and compare the stats based entirely on equivalent weight/BMI I you will find nearly all differences would disappear.

This is not only false, but dangerously false. We are in the process of discovering that certain classes of popularly-prescribed drugs (eg ACE inhibitors for blacks, certain chemotherapy drugs for Asians) are ineffective or even toxic for populations not represented in the relevant drug development research cohorts. It's not identity politics to note that pharmacokinetics can differ between individuals and populations. These differences do not explain all of the population-level morbidity and mortality differences between ethnicities, but they are significant when investigating differences between groups on the same course of treatment.

marchenko··on An Impenetrable Program Transforming How Courts Treat DNA Evidence
Every step of the judicial process should be completely open to scrutiny in every particular by the accused and in general (eg exact methods) by any motivated citizen. This transparency is more important to the long-term viability of our legal system than extra accuracy provided by a proprietary algorithm. It is possible that this analysis is not amenable to monetization at the level necessary to sustain private investment, which is a different problem.
marchenko··on Stats without Tears (2016)
> References TI-83 or TI-84 feel dated.

Now I feel dated. I think there are a few of these still circulating through the younger branches of my family.

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