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USA tops International Math Olympiad for first time in 21 years

141 points by tokenadult 11y ago

tokenadult 11y ago
I think the reporting from The Guardian a few days earlier,[1] mentioned in this article, provides some good perspective on the International Mathematics Olympiad (IMO) from across the Atlantic Ocean from this Washington Post report. [1] http://www.theguardian.com/science/2015/jul/15/us-wins-hardest-ever-international-maths-olympiad http://www.theguardian.com/science/2015/jul/15/us-wins-harde...
adamdavid 11y ago
IF economic trends are any indicator, those kids have a very bright, prosperous future ahead of them.
helmett 11y ago
congratulation...I see a hedge fund career for many
- wbhart 11y ago
  A good proportion of maths olympians go into mathematics in academia rather than into industry. Industry does need problem solvers, but maths olympians develop creativity and a sense of elegance and beauty as well. Industry requires efficient solutions to technical problems, more than elegant or beautiful ones, at least relative to what is possible with full academic freedom.
  - madez 11y ago
    As a minor nitpick, some mathematicians see elegance in efficient solutions. It's interesting to get your head around a specific problem and come up with the solution that is optimal regarding some given metric. However, I agree that industry and mathematics are not best friends. That's because mathematicians righteously demand and require a level of freedom and support the industry is not always willing to give because of the social problem it creates with other employees and because the value of the work of a mathematician can be too hard to judge. From my experience, the fight to get the working conditions you need is not worth it. My advise to fellow mathematicians is that — when you want go into the industry — to go where there are already mathematicians.
    - wbhart 11y ago
      Just to clarify, I meant efficient from the perspective of business, not efficient from the perspective of mathematics. In industry, often a solution which "works", but is neither mathematically "efficient" or "elegant" is "good enough". By and large, industry is trying to generate revenue, not scientific knowledge.
  - jcrites 11y ago
    In software engineering, elegance is prized and is often related to efficiency in several layers. At the human layer, one expression of this idea is the principle of least astonishment: "People are part of the system. The design should match the user's experience, expectations, and mental models." (Wikipedia). A system involving people is not efficient if the people are often surprised by its design, implementation, or behavior. Efficient software solutions also tend to involve elegance. Take Git for example as an improvement over other source control systems. The conceptual primitives that Git is built upon are elegant and recognizing them as the correct basis for source control (along with a strong implementation) resulted in Git's efficiency and power. Granted, software is different from mathematics, but I find the parallel interesting. I suspect that a mathematician's desire to find an elegant formulation, and appreciation of it, is very similar to the software engineer's.
  - giech 11y ago
    My anecdotal experience is that most may start with math for their first degree, but then (or during) pivot to some related but more applied area like CS, Econ, etc.
- overpaidgoogler 11y ago
  I hope not. When I did math Olympiads (including the IMO) I was presented with a false dichotomy of pure math or finance. This is really unfortunate because finance in general does not use very deep math. A tiny number of people might use SDEs but by now the techniques are standard and boring anyway. Furthermore, even mainstream economists doubt that this sort of finance has positive externalities. The amount of resources that go into finance is just way out of proportion to what seems necessary for price discovery. In contrast, all of the science and engineering disciplines can make use of very interesting math. Not deep compared to research math, but used in a much more interesting way than in finance. E.g when you study the statistics of markets, you are just playing a game, and don't care that much about external reality per se. On the other hand if you study the statistics of DNA or gene expression, you are doing real science. I think the best advice to a young person studying math is what was given to me at the age when I was doing the IMO (and interestingly, after I graduated by someone else): Don't neglect statistics.
  - rtpg 11y ago
    As someone who neglected statistics as a student ( topology was a lot funner) , would you have any recommendations for self-learning tools for statistics?
    - overpaidgoogler 11y ago
      I would suggest "elements of statistical learning". If possible I would also try to study some econometrics which gives unparalleled insight into the correlation vs causation issue. You can think of econometrics as a branch of statistics that remained separate from the mainstream for historical reasons.
    - chestervonwinch 11y ago
      Casella & Berger's "Statistical Inference" is a nice introduction to basic probability theory and statistics. I found it pretty readable, and it's used for many 1st year graduate stat programs. Duda & Hart's "Pattern Classification" is one of the best introductions to machine learning IMO. It assumes very little in the way prerequisites, which is nice for first time exposure. Hastie & Tibshirani's "Elements of Statistical Learning" can be a little intimidating without having been exposed to the ideas of the previous two texts. Afterwards, however, it is a gem.
- netvarun 11y ago
  There was an interesting article that looked at what the USA Mathematical olympiad trainee candidates in 1980 were doing now (This batch included the famous Noam Elkies) - http://andrewgelman.com/2015/03/17/1980-math-olympiad-program-now/ http://andrewgelman.com/2015/03/17/1980-math-olympiad-progra... HN Discussion: https://news.ycombinator.com/item?id=9225683 https://news.ycombinator.com/item?id=9225683 A bunch of them went into academia, though not necessarily pure math. Some became engineers and only one ended up in finance.
vixen99 11y ago
Astonishing performance (3rd place) by North Korea with pop. around 25m. Not sure what incentives were in place for the contestants.
- gjm11 11y ago
  South Korea, according to the article.
- timt51 11y ago
  North Korea in 4th place: https://www.imo-official.org/year_country_r.aspx?year=2015 https://www.imo-official.org/year_country_r.aspx?year=2015
- desdiv 11y ago
  North Korea was caught cheating twice, and is the only country to have been caught cheating at the IMOs so far, so I would take their ranking with a grain of salt. [0] https://en.wikipedia.org/wiki/List_of_International_Mathematical_Olympiads https://en.wikipedia.org/wiki/List_of_International_Mathemat...
  - _asummers 11y ago
    How does one cheat at a test of this sort?
    - DanBC 11y ago
      Team leaders know the question in advance. They are seperated from the team, but if they want to communicate they can. http://www.quora.com/How-did-North-Korea-cheat-in-the-IMO-in-1991-and-2010 http://www.quora.com/How-did-North-Korea-cheat-in-the-IMO-in... Edit: have a read of this page. It shows that marking is not just a case of comparing the answer papers with a pre-prepared answer script. There is discussion and debate involved. http://www.imo-register.org.uk/2010-report.html http://www.imo-register.org.uk/2010-report.html > Problem 4 was the second geometry problem, and so I led. We agreed four 7s straight away. The disputes were that I wanted a 7 for Luke Betts, and the co-ordinators were only offering 3 because they thought that there was a hole in his argument. On the other hand, they wanted to give Andrew Carlotti a 7 but I was only prepared to take 3. I explained to them the weakness in Carlotti’s argument, and they looked a little surprised. I asked them about the alleged weakness in Betts’s script, and I couldn’t understand what they were worried about. I suggested an overnight adjournment so that we could both make detailed preparations, and we met again the next day.
enimodas 11y ago
I looked a bit at the gender distribution for the gold and silver medalists, I would guess only 1 in 10-20 is a girl, most seemed to be from the eastern bloc countries.
- kelukelugames 11y ago
  This is an objective statement that provides data. Please don't down vote it.
- nemoniac 11y ago
  Congratulations to Ukraine and Bosnia-Herzegovina for being the only countries to send gender-balanced teams of three boys and three girls.
  - ratsmack 11y ago
    Are you implying that it would be good if the ones sent were based on a gender balance rather than being chosen on their math ability?
    - lwhalen 11y ago
      It's far preferable to be politically correct than to win, don'tcha know. /s
    - veridies 11y ago
      He might be suggesting that Ukraine and Bosnia-Herzegovina are to be lauded for having an educational system that doesn't end up leaving half of the population behind.
      - throwit542 11y ago
        You're talking about the U.S. educational system leaving men behind, right? Because in America, women are more likely to graduate high school [0], enroll in college [1], graduate from college [2], and even make up 3/5's of graduate students [2]. [0] http://www.infoplease.com/ipa/A0779196.html http://www.infoplease.com/ipa/A0779196.html [1] http://www.pewresearch.org/fact-tank/2014/03/06/womens-college-enrollment-gains-leave-men-behind/ http://www.pewresearch.org/fact-tank/2014/03/06/womens-colle... [2] http://www.prb.org/Publications/Articles/2011/gender-gap-in-education.aspx http://www.prb.org/Publications/Articles/2011/gender-gap-in-...
kafkaesque 11y ago
This is definitely off-topic, but have people taken a look at Po-Shen Loh's company expii.com? He's the coach for the US team. It says: Expii is a collection of free, interactive, explanations written by people from around the world Interesting!
- delish 11y ago
  I gasped when I saw my acquaintance's name on HN. By coincidence, I'm wearing an expii t-shirt right now. He's really nice, and excited about improving math and science education. Expii could be called an "explorable explanations" Wikipedia[0]--one can write code (I think a subset of JS), embed videos etc in service of a better explanation. I'm also fond of him because his office has an X server (or would that be X client?). How many startups actually use X?? [0] Just my two cents.
  - bjwbell 11y ago
    Maybe I'm just dense. Do you mean X11 server (https://en.wikipedia.org/wiki/X_Window_System https://en.wikipedia.org/wiki/X_Window_System) or something else?
    - delish 11y ago
      Indeed X11. what I meant by my X11 server/client waffling is I think you /run/ an X11 client and servers connect to it--this is backwards to every other usage of client/server.
- expii 11y ago
  Thanks for noticing! :) Indeed, I've been working with a certain segment of the population through my roles as the national coach of the USA IMO team and as a math professor at Carnegie Mellon University. However, after being appointed to the national coach position, I realized that the USA would not be able to consistently deliver top results unless we lifted our mathematical level across a broad base. It seemed that technology could provide the solution to that problem, in the sense that it's possible to crowd-source the scripting of automatic virtual tutors, which can then be replayed (for free) on mobile devices throughout all regions, rich or poor. Thus, expii.com was born. https://www.youtube.com/watch?v=11SdySDDrMk https://www.youtube.com/watch?v=11SdySDDrMk https://www.youtube.com/watch?v=t6WVbFIz43M https://www.youtube.com/watch?v=t6WVbFIz43M -- Po-Shen Loh
kelukelugames 11y ago
This makes me want to chant USA a lot more than the soccer game.
- ams6110 11y ago
  Something about this comment really annoys me. It's like you are disparaging high achievement by others just because it's not in a field you are personally interested in?
  - kelukelugames 11y ago
    No I like sports. It's just boring when team USA wins again because they are always so dominant. Winning once in 21 years makes us the underdog. Getting really annoyed is silly. I try not to be easily offended by hackernews comments.
- enlightenedfool 11y ago
  or you could learn math & science...way better
  - kelukelugames 11y ago
    Actually my team from Cupertino was county champ in Math Counts and 2nd in the state. We lost to the team we beat in counties because they went through a training montage to avenge their loss. ;)
archlight 11y ago
it is a good news. because American become more confident in educating their kids in maths and abandon the idea that you can be lawyer if you are not good at math. on the other hand, Chinese can stop believing that math is highest form of intelligence and pursue career as lawyer etc.
- bilbo0s 11y ago
  ??? Wouldn't it be better for mankind ... if as many people like these kids as possible pursued math and science more vigorously ??? Especially kids like these, who have what I would term "creative" intelligence. Why would we want those people in law ??? That gives us far less than having them in math and science. And we will get the MOST by having them in art AND math and science. Then we'd really get their creativity going as they look for solutions to problems.
  - Retric 11y ago
    IMO, high level Math and Science is generally a waste of a lot of really smart peoples time. The LHC for example is studying particle energy's so far outside of 'reasonable' that we are not going to get useful technology from there. The same is true of a lot of esoteric Math which mostly ends up divorced from anything actually useful. That's not to say funding such things is necessarily a waste, just the focus on STEM education may be excessive. Russia for example ended up with a lot of highly educated security guards.
    - gus_massa 11y ago
      The standard example of unexpected esoteric physic application is the Special and General Relativity corrections of the GPS. 100 years ago nobody thought that we would ever use that small correction or that everybody would have a special-and-general-aware device in the pocket. Another cool application is the superconductors in the NMR devices. They can see what is inside your head and even do something equivalent to a chemical analysis (with NRM spectroscopy) without opening it. The first superconductors experiments used Helium at 4K, so they were only a laboratory curiosity. For everyday use, I like the giant magnetoresistance. This is my favorite case to explain that strange quantum effects have real world direct applications. Just start talking about the spin in electrons. Then explain that some magnetic conductors have a different value of the current with spin up and the currents with spin down. Then add the sandwich with non-magnetic conductors. At this moment it looks like a weird laboratory experiment. Then suddenly explain how it is used in hard disks heads: http://en.wikipedia.org/wiki/Giant_magnetoresistance http://en.wikipedia.org/wiki/Giant_magnetoresistance
lacker 11y ago
Congrats to the team! I'm curious if any of the six team members are reading HN.
- ryanalweiss 11y ago
  Hi. :)
Grue3 11y ago
Russia nowhere to be seen. We used to be a powerhouse too, but it seems the education here is in absolute shambles now.
- lacker 11y ago
  To be fair, this contest measures the performance of six people. The education that is most directly tied to IMO performance is specific "math for the top few students in the country" stuff which is usually some specialist math camp thing. So I don't think it necessarily means that much about a whole country's math education, if their IMO team doesn't do well.
  - vph 11y ago
    Don't know about other countries. But in the USA, the six people who make the team are selected among high schoolers after rounds of competition. It does reflect very much a country's math education. But math education is just part of a much larger equation.
giech 11y ago
Not related to this year's competition, but you may also be interested in the hall of fame [1], which contains many well-known names. [1] https://www.imo-official.org/hall.aspx https://www.imo-official.org/hall.aspx
bjwbell 11y ago
What's happened to Germany? They used to be one of the best in mathematics. But the recent IMO results are very poor (27th this year). Has their education system declined or something else perhaps? I know they have a low birthrate....
datamingle 11y ago
A Canadian got a perfect score. Only one I found while checking around. No American nor Chinese got a perfect score. https://www.imo-official.org/participant_r.aspx?id=19624 https://www.imo-official.org/participant_r.aspx?id=19624 Also, only 1 person got 3 perfect scores in the history of the event: Ciprian Manolescu (3 for 3 perfect) https://www.imo-official.org/participant_r.aspx?id=3789 https://www.imo-official.org/participant_r.aspx?id=3789
graycat 11y ago
For Problem 6 given in the OP, the claim is false: Notation: We borrow subscript and superscript notation from D. Knuth's TeX. So, a with a subscript j is written a_j. Consider the simple graph, based just on typing, below. The graph shows the first four values of a specific sequence a_j. This sequence is a contradiction to claim of Problem 6. In this graph, the values of j = 1, 2, ... are plotted on the horizontal axis with 1, 2, ..., and the values of the a_j are plotted on the vertical axis from 1 to 2015. We plot a value of a_j as just 'a'. Due to constraint (ii), we indicate by 'x' points that, due to prior values of a_j, cannot have an 'a'. So, the graph is: 2015 . . . a_j . 5 4 3 a a 2 x x ... 1 axax 123456789 j Then the first two terms of the sequence a_j are: a_1 = 3 a_2 = 1 and generally for j = 1, 2, ..., a_j is: / | 3 if j is odd | a_j = < | | 1 if j is even \ Then for any positive integer b and j = 1, 2, ... (a_j - b) + (a_{j + 1} - b) >= 2 More generally for positive integers m and k, sum_{j = m + 1}^{m + 2k} (a_j - b) >= 2 k Then for any positive integer N, we can set m = N and n = m + 2(1007^2) and get | sum_{j=m+1}^n (a_j - b) | = sum_{j=m+1}^n (a_j - b) = 2 (1007^2) > 1007^2 showing that the claim is false.
- paulfr 11y ago
  There are no absolute values in the summands, so in your example pairs of consecutive terms sum to 0 when you choose b = 2. The theorem seems entirely correct to me. You can prove it with these sub-steps: (1) the set of all j + a_j is the set of nonnegative integers minus a finite number of gaps (2) thus for large enough n you can express \sum_{j=1}^n (j + a_j) as a quadratic function of n, plus a residual term e(n) of magnitude at most 1007^2/2 (3) more precisely, \sum_{j=m+1}^n a_j = g (n-m) + e(n) - e(m) where g is the number of gaps in (1) Then choosing b = g solves the problem. Hope that helps.

141 points by tokenadult 11y ago

I think the reporting from The Guardian a few days earlier,[1] mentioned in this article, provides some good perspective on the International Mathematics Olympiad (IMO) from across the Atlantic Ocean from this Washington Post report. [1] http://www.theguardian.com/science/2015/jul/15/us-wins-hardest-ever-international-maths-olympiad http://www.theguardian.com/science/2015/jul/15/us-wins-harde...

adamdavid 11y ago

IF economic trends are any indicator, those kids have a very bright, prosperous future ahead of them.

helmett 11y ago

congratulation...I see a hedge fund career for many

wbhart 11y ago
A good proportion of maths olympians go into mathematics in academia rather than into industry. Industry does need problem solvers, but maths olympians develop creativity and a sense of elegance and beauty as well. Industry requires efficient solutions to technical problems, more than elegant or beautiful ones, at least relative to what is possible with full academic freedom.
- madez 11y ago
  As a minor nitpick, some mathematicians see elegance in efficient solutions. It's interesting to get your head around a specific problem and come up with the solution that is optimal regarding some given metric. However, I agree that industry and mathematics are not best friends. That's because mathematicians righteously demand and require a level of freedom and support the industry is not always willing to give because of the social problem it creates with other employees and because the value of the work of a mathematician can be too hard to judge. From my experience, the fight to get the working conditions you need is not worth it. My advise to fellow mathematicians is that — when you want go into the industry — to go where there are already mathematicians.
  - wbhart 11y ago
    Just to clarify, I meant efficient from the perspective of business, not efficient from the perspective of mathematics. In industry, often a solution which "works", but is neither mathematically "efficient" or "elegant" is "good enough". By and large, industry is trying to generate revenue, not scientific knowledge.
- jcrites 11y ago
  In software engineering, elegance is prized and is often related to efficiency in several layers. At the human layer, one expression of this idea is the principle of least astonishment: "People are part of the system. The design should match the user's experience, expectations, and mental models." (Wikipedia). A system involving people is not efficient if the people are often surprised by its design, implementation, or behavior. Efficient software solutions also tend to involve elegance. Take Git for example as an improvement over other source control systems. The conceptual primitives that Git is built upon are elegant and recognizing them as the correct basis for source control (along with a strong implementation) resulted in Git's efficiency and power. Granted, software is different from mathematics, but I find the parallel interesting. I suspect that a mathematician's desire to find an elegant formulation, and appreciation of it, is very similar to the software engineer's.
- giech 11y ago
  My anecdotal experience is that most may start with math for their first degree, but then (or during) pivot to some related but more applied area like CS, Econ, etc.
overpaidgoogler 11y ago
I hope not. When I did math Olympiads (including the IMO) I was presented with a false dichotomy of pure math or finance. This is really unfortunate because finance in general does not use very deep math. A tiny number of people might use SDEs but by now the techniques are standard and boring anyway. Furthermore, even mainstream economists doubt that this sort of finance has positive externalities. The amount of resources that go into finance is just way out of proportion to what seems necessary for price discovery. In contrast, all of the science and engineering disciplines can make use of very interesting math. Not deep compared to research math, but used in a much more interesting way than in finance. E.g when you study the statistics of markets, you are just playing a game, and don't care that much about external reality per se. On the other hand if you study the statistics of DNA or gene expression, you are doing real science. I think the best advice to a young person studying math is what was given to me at the age when I was doing the IMO (and interestingly, after I graduated by someone else): Don't neglect statistics.
- rtpg 11y ago
  As someone who neglected statistics as a student ( topology was a lot funner) , would you have any recommendations for self-learning tools for statistics?
  - overpaidgoogler 11y ago
    I would suggest "elements of statistical learning". If possible I would also try to study some econometrics which gives unparalleled insight into the correlation vs causation issue. You can think of econometrics as a branch of statistics that remained separate from the mainstream for historical reasons.
  - chestervonwinch 11y ago
    Casella & Berger's "Statistical Inference" is a nice introduction to basic probability theory and statistics. I found it pretty readable, and it's used for many 1st year graduate stat programs. Duda & Hart's "Pattern Classification" is one of the best introductions to machine learning IMO. It assumes very little in the way prerequisites, which is nice for first time exposure. Hastie & Tibshirani's "Elements of Statistical Learning" can be a little intimidating without having been exposed to the ideas of the previous two texts. Afterwards, however, it is a gem.
netvarun 11y ago
There was an interesting article that looked at what the USA Mathematical olympiad trainee candidates in 1980 were doing now (This batch included the famous Noam Elkies) - http://andrewgelman.com/2015/03/17/1980-math-olympiad-program-now/ http://andrewgelman.com/2015/03/17/1980-math-olympiad-progra... HN Discussion: https://news.ycombinator.com/item?id=9225683 https://news.ycombinator.com/item?id=9225683 A bunch of them went into academia, though not necessarily pure math. Some became engineers and only one ended up in finance.

vixen99 11y ago

Astonishing performance (3rd place) by North Korea with pop. around 25m. Not sure what incentives were in place for the contestants.

gjm11 11y ago
South Korea, according to the article.
timt51 11y ago
North Korea in 4th place: https://www.imo-official.org/year_country_r.aspx?year=2015 https://www.imo-official.org/year_country_r.aspx?year=2015
desdiv 11y ago
North Korea was caught cheating twice, and is the only country to have been caught cheating at the IMOs so far, so I would take their ranking with a grain of salt. [0] https://en.wikipedia.org/wiki/List_of_International_Mathematical_Olympiads https://en.wikipedia.org/wiki/List_of_International_Mathemat...
- _asummers 11y ago
  How does one cheat at a test of this sort?
  - DanBC 11y ago
    Team leaders know the question in advance. They are seperated from the team, but if they want to communicate they can. http://www.quora.com/How-did-North-Korea-cheat-in-the-IMO-in-1991-and-2010 http://www.quora.com/How-did-North-Korea-cheat-in-the-IMO-in... Edit: have a read of this page. It shows that marking is not just a case of comparing the answer papers with a pre-prepared answer script. There is discussion and debate involved. http://www.imo-register.org.uk/2010-report.html http://www.imo-register.org.uk/2010-report.html > Problem 4 was the second geometry problem, and so I led. We agreed four 7s straight away. The disputes were that I wanted a 7 for Luke Betts, and the co-ordinators were only offering 3 because they thought that there was a hole in his argument. On the other hand, they wanted to give Andrew Carlotti a 7 but I was only prepared to take 3. I explained to them the weakness in Carlotti’s argument, and they looked a little surprised. I asked them about the alleged weakness in Betts’s script, and I couldn’t understand what they were worried about. I suggested an overnight adjournment so that we could both make detailed preparations, and we met again the next day.

enimodas 11y ago

I looked a bit at the gender distribution for the gold and silver medalists, I would guess only 1 in 10-20 is a girl, most seemed to be from the eastern bloc countries.

kelukelugames 11y ago
This is an objective statement that provides data. Please don't down vote it.
nemoniac 11y ago
Congratulations to Ukraine and Bosnia-Herzegovina for being the only countries to send gender-balanced teams of three boys and three girls.
- ratsmack 11y ago
  Are you implying that it would be good if the ones sent were based on a gender balance rather than being chosen on their math ability?
  - lwhalen 11y ago
    It's far preferable to be politically correct than to win, don'tcha know. /s
  - veridies 11y ago
    He might be suggesting that Ukraine and Bosnia-Herzegovina are to be lauded for having an educational system that doesn't end up leaving half of the population behind.
    - throwit542 11y ago
      You're talking about the U.S. educational system leaving men behind, right? Because in America, women are more likely to graduate high school [0], enroll in college [1], graduate from college [2], and even make up 3/5's of graduate students [2]. [0] http://www.infoplease.com/ipa/A0779196.html http://www.infoplease.com/ipa/A0779196.html [1] http://www.pewresearch.org/fact-tank/2014/03/06/womens-college-enrollment-gains-leave-men-behind/ http://www.pewresearch.org/fact-tank/2014/03/06/womens-colle... [2] http://www.prb.org/Publications/Articles/2011/gender-gap-in-education.aspx http://www.prb.org/Publications/Articles/2011/gender-gap-in-...

kafkaesque 11y ago

This is definitely off-topic, but have people taken a look at Po-Shen Loh's company expii.com? He's the coach for the US team. It says: Expii is a collection of free, interactive, explanations written by people from around the world Interesting!

delish 11y ago
I gasped when I saw my acquaintance's name on HN. By coincidence, I'm wearing an expii t-shirt right now. He's really nice, and excited about improving math and science education. Expii could be called an "explorable explanations" Wikipedia[0]--one can write code (I think a subset of JS), embed videos etc in service of a better explanation. I'm also fond of him because his office has an X server (or would that be X client?). How many startups actually use X?? [0] Just my two cents.
- bjwbell 11y ago
  Maybe I'm just dense. Do you mean X11 server (https://en.wikipedia.org/wiki/X_Window_System https://en.wikipedia.org/wiki/X_Window_System) or something else?
  - delish 11y ago
    Indeed X11. what I meant by my X11 server/client waffling is I think you /run/ an X11 client and servers connect to it--this is backwards to every other usage of client/server.
expii 11y ago
Thanks for noticing! :) Indeed, I've been working with a certain segment of the population through my roles as the national coach of the USA IMO team and as a math professor at Carnegie Mellon University. However, after being appointed to the national coach position, I realized that the USA would not be able to consistently deliver top results unless we lifted our mathematical level across a broad base. It seemed that technology could provide the solution to that problem, in the sense that it's possible to crowd-source the scripting of automatic virtual tutors, which can then be replayed (for free) on mobile devices throughout all regions, rich or poor. Thus, expii.com was born. https://www.youtube.com/watch?v=11SdySDDrMk https://www.youtube.com/watch?v=11SdySDDrMk https://www.youtube.com/watch?v=t6WVbFIz43M https://www.youtube.com/watch?v=t6WVbFIz43M -- Po-Shen Loh

kelukelugames 11y ago

This makes me want to chant USA a lot more than the soccer game.

ams6110 11y ago
Something about this comment really annoys me. It's like you are disparaging high achievement by others just because it's not in a field you are personally interested in?
- kelukelugames 11y ago
  No I like sports. It's just boring when team USA wins again because they are always so dominant. Winning once in 21 years makes us the underdog. Getting really annoyed is silly. I try not to be easily offended by hackernews comments.
enlightenedfool 11y ago
or you could learn math & science...way better
- kelukelugames 11y ago
  Actually my team from Cupertino was county champ in Math Counts and 2nd in the state. We lost to the team we beat in counties because they went through a training montage to avenge their loss. ;)

archlight 11y ago

it is a good news. because American become more confident in educating their kids in maths and abandon the idea that you can be lawyer if you are not good at math. on the other hand, Chinese can stop believing that math is highest form of intelligence and pursue career as lawyer etc.

bilbo0s 11y ago
??? Wouldn't it be better for mankind ... if as many people like these kids as possible pursued math and science more vigorously ??? Especially kids like these, who have what I would term "creative" intelligence. Why would we want those people in law ??? That gives us far less than having them in math and science. And we will get the MOST by having them in art AND math and science. Then we'd really get their creativity going as they look for solutions to problems.
- Retric 11y ago
  IMO, high level Math and Science is generally a waste of a lot of really smart peoples time. The LHC for example is studying particle energy's so far outside of 'reasonable' that we are not going to get useful technology from there. The same is true of a lot of esoteric Math which mostly ends up divorced from anything actually useful. That's not to say funding such things is necessarily a waste, just the focus on STEM education may be excessive. Russia for example ended up with a lot of highly educated security guards.
  - gus_massa 11y ago
    The standard example of unexpected esoteric physic application is the Special and General Relativity corrections of the GPS. 100 years ago nobody thought that we would ever use that small correction or that everybody would have a special-and-general-aware device in the pocket. Another cool application is the superconductors in the NMR devices. They can see what is inside your head and even do something equivalent to a chemical analysis (with NRM spectroscopy) without opening it. The first superconductors experiments used Helium at 4K, so they were only a laboratory curiosity. For everyday use, I like the giant magnetoresistance. This is my favorite case to explain that strange quantum effects have real world direct applications. Just start talking about the spin in electrons. Then explain that some magnetic conductors have a different value of the current with spin up and the currents with spin down. Then add the sandwich with non-magnetic conductors. At this moment it looks like a weird laboratory experiment. Then suddenly explain how it is used in hard disks heads: http://en.wikipedia.org/wiki/Giant_magnetoresistance http://en.wikipedia.org/wiki/Giant_magnetoresistance

lacker 11y ago

Congrats to the team! I'm curious if any of the six team members are reading HN.

ryanalweiss 11y ago
Hi. :)

Grue3 11y ago

Russia nowhere to be seen. We used to be a powerhouse too, but it seems the education here is in absolute shambles now.

lacker 11y ago
To be fair, this contest measures the performance of six people. The education that is most directly tied to IMO performance is specific "math for the top few students in the country" stuff which is usually some specialist math camp thing. So I don't think it necessarily means that much about a whole country's math education, if their IMO team doesn't do well.
- vph 11y ago
  Don't know about other countries. But in the USA, the six people who make the team are selected among high schoolers after rounds of competition. It does reflect very much a country's math education. But math education is just part of a much larger equation.

giech 11y ago

Not related to this year's competition, but you may also be interested in the hall of fame [1], which contains many well-known names. [1] https://www.imo-official.org/hall.aspx https://www.imo-official.org/hall.aspx

bjwbell 11y ago

What's happened to Germany? They used to be one of the best in mathematics. But the recent IMO results are very poor (27th this year). Has their education system declined or something else perhaps? I know they have a low birthrate....

datamingle 11y ago

A Canadian got a perfect score. Only one I found while checking around. No American nor Chinese got a perfect score. https://www.imo-official.org/participant_r.aspx?id=19624 https://www.imo-official.org/participant_r.aspx?id=19624 Also, only 1 person got 3 perfect scores in the history of the event: Ciprian Manolescu (3 for 3 perfect) https://www.imo-official.org/participant_r.aspx?id=3789 https://www.imo-official.org/participant_r.aspx?id=3789

graycat 11y ago

For Problem 6 given in the OP, the claim is false: Notation: We borrow subscript and superscript notation from D. Knuth's TeX. So, a with a subscript j is written a_j. Consider the simple graph, based just on typing, below. The graph shows the first four values of a specific sequence a_j. This sequence is a contradiction to claim of Problem 6. In this graph, the values of j = 1, 2, ... are plotted on the horizontal axis with 1, 2, ..., and the values of the a_j are plotted on the vertical axis from 1 to 2015. We plot a value of a_j as just 'a'. Due to constraint (ii), we indicate by 'x' points that, due to prior values of a_j, cannot have an 'a'. So, the graph is: 2015 . . . a_j . 5 4 3 a a 2 x x ... 1 axax 123456789 j Then the first two terms of the sequence a_j are: a_1 = 3 a_2 = 1 and generally for j = 1, 2, ..., a_j is: / | 3 if j is odd | a_j = < | | 1 if j is even \ Then for any positive integer b and j = 1, 2, ... (a_j - b) + (a_{j + 1} - b) >= 2 More generally for positive integers m and k, sum_{j = m + 1}^{m + 2k} (a_j - b) >= 2 k Then for any positive integer N, we can set m = N and n = m + 2(1007^2) and get | sum_{j=m+1}^n (a_j - b) | = sum_{j=m+1}^n (a_j - b) = 2 (1007^2) > 1007^2 showing that the claim is false.

paulfr 11y ago
There are no absolute values in the summands, so in your example pairs of consecutive terms sum to 0 when you choose b = 2. The theorem seems entirely correct to me. You can prove it with these sub-steps: (1) the set of all j + a_j is the set of nonnegative integers minus a finite number of gaps (2) thus for large enough n you can express \sum_{j=1}^n (j + a_j) as a quadratic function of n, plus a residual term e(n) of magnitude at most 1007^2/2 (3) more precisely, \sum_{j=m+1}^n a_j = g (n-m) + e(n) - e(m) where g is the number of gaps in (1) Then choosing b = g solves the problem. Hope that helps.