Блог пользователя DemoVersion

Автор DemoVersion, 10 лет назад, По-английски

Due there isn't any official country ranking for IOI and i was wondering of The position of Iran in this tournament based on the total points , I grabbed info from table in IOI2014 Official Websites Ranking and Done some coding,Moving to Excel and finnaly I gained Top10 Countries Summary Ranking:

IOI 2014 Country Ranking Summary

Then i decided to attach each participant name,ranking to his/her country for more information and share it on The Codeforces ...

Top 20 Countries With Details (PNG Picture) 0.7 MB

All Countries With Details (PNG Picture) 2.7 MB

Congratulate IRAN IOI Team

Any suggestion/error report in standings will be welcome.

UPD: There is some errors in medals color but Countries ranking is based on the total points and doesn't change, If somebody give me the right scores for medalists surely i will update the photos

UPD2: I sync medalist with the information in stats.ioinformatics.org no change in Top10 , If you still seeing the previous images refresh cause its exactly the same URL

Also i noticed that I'm not the only one made mistakes for medalists also CodeChef congratulate 1Gold 1Silve 1Bronze in their last email sent to members but this website says they have got 1Gold 1Silver excluding that Bronze

  • Проголосовать: нравится
  • +21
  • Проголосовать: не нравится

»
10 лет назад, # |
  Проголосовать: нравится +6 Проголосовать: не нравится

Good job, you can also see results by medals/points for countries here

  • »
    »
    10 лет назад, # ^ |
      Проголосовать: нравится +5 Проголосовать: не нравится

    Or here.

  • »
    »
    10 лет назад, # ^ |
      Проголосовать: нравится +11 Проголосовать: не нравится

    Thanks , I didn't see any before ... But total points is more fair i guess ...

    • »
      »
      »
      10 лет назад, # ^ |
        Проголосовать: нравится +5 Проголосовать: не нравится

      Total points is definitely more fair. Ranking a country that had one barely gold medalist and 3 nothings better than one with 4 almost gold medalists is ridiculous.

      Olympic ranking is only useful in case there are multiple categories, so you can't go by points / total achievements. Which isn't the case here.

      • »
        »
        »
        »
        10 лет назад, # ^ |
          Проголосовать: нравится 0 Проголосовать: не нравится

        There is so much views and definitely none of them right, each got its reasons.

        Ex. There is more than 380 views of my summary photo, more than 100 downloads for two photo, Topic rating goes like 5*sin(t) :D

        • »
          »
          »
          »
          »
          10 лет назад, # ^ |
            Проголосовать: нравится +3 Проголосовать: не нравится

          But we can still say that ranking by total points (in case it's possible — there's just 1 category and there are clear points in it) reflects a country's performance better than ranking just by medals.

          • »
            »
            »
            »
            »
            »
            10 лет назад, # ^ |
            Rev. 3   Проголосовать: нравится 0 Проголосовать: не нравится

            Yes that's Ambiguous and i avoid using that ...

            I see they do :

            • Sort by total medals
            • Sort by Gold*3 + Silver*2 + Bronze
            • Sort by Gold , if equal Silver ,if two equal Bronze

            I invite everybody to solve UVA 10997 — Medals its a funny problem related.

            • »
              »
              »
              »
              »
              »
              »
              10 лет назад, # ^ |
              Rev. 3   Проголосовать: нравится +14 Проголосовать: не нравится

              I can only repeat: it's not good to use medals at all in case points are available, because one point can make a relatively large difference in ranking.

              A case when this approach fails: country A gets 1 weak gold, 3 weak bronzes; country B 3 strong silvers and 1 nothing. Neither of these 3 comparisons puts country B before country A, but there's just 1 point difference between G/S and B/nothing, so 2 pairs of people (G/S, B/nothing) can be 1 point away and what's left is 2 weak B (A) vs 2 strong S (B), so B is clearly much better than A.

              If Syria got the visa (joke related to IOI 2013, where Australia probably would've had 1 gold if they gave the visa to Syria), there could've been 1 more gold and bronze for country B, which would make it 1G,3B for A and 1G,2S,1B for B. [insert trollface here] [insert facepalm here] on my way to make a trollfacepalm

              Also, Czech team at IMO had scores 18/20/20/21/21/24; of course, silver medals were only from 22 points (and Slovaks also had a 21-pointer). Serves as a good example.

              • »
                »
                »
                »
                »
                »
                »
                »
                10 лет назад, # ^ |
                  Проголосовать: нравится -12 Проголосовать: не нравится

                Stop telling this offensive joke about Syria. I don't see any need to associate the event of denying Syrian students visas with any joke, regardless of its purpose. Besides, Syrian students could have beaten your alleged country B bronze medalists, so your argument makes little sense.

                • »
                  »
                  »
                  »
                  »
                  »
                  »
                  »
                  »
                  10 лет назад, # ^ |
                  Rev. 2   Проголосовать: нравится +12 Проголосовать: не нравится

                  "Stop telling" wait, did I mention it before?

                  The joke isn't on Syria, it's on Australia — there were about 3 or 4 events such that each could've resulted in the best silver, which happened to be from Australia, to get gold, one of which was Syria participating, because it'd increase the number of gold medals (I wasn't implying that Syria wouldn't get any medal, that was just a coincidence — and you probably agree that Syria wouldn't have had gold).

                  Well, sorry if you got offended by it, but I still don't find the fact that Australia basically denied itself gold any less funny. If you mind it too much, just imagine that I said Mars or something ¯(°_o)/¯

    • »
      »
      »
      10 лет назад, # ^ |
        Проголосовать: нравится +3 Проголосовать: не нравится

      SnarkNews has this type of sorting available as well.

»
10 лет назад, # |
  Проголосовать: нравится +4 Проголосовать: не нравится

Your silver cut-off is wrong. You marked it as 341 points and above, whereas the real cut-off is 323 points and above.

  • »
    »
    10 лет назад, # ^ |
    Rev. 3   Проголосовать: нравится 0 Проголосовать: не нравится
    int Lg=308/12;
    int Ls=308*3/12;
    int Lb=308*6/12;
    

    They define the last position of the each medal , Is that wrong?

    UPD: Read Post Again Its Fixed

    • »
      »
      »
      10 лет назад, # ^ |
        Проголосовать: нравится +3 Проголосовать: не нравится

      Yes.

      • The score necessary to achieve a gold medal is the largest score such that at least one twelfth of all contestants receive a gold medal.
      • The score necessary to achieve a silver medal is the largest score such that at least one sixth of all contestants receive a silver medal.
      • The score necessary to achieve a bronze medal is the smallest score such that at most one half of all contestants receive a medal.
      • »
        »
        »
        »
        10 лет назад, # ^ |
          Проголосовать: нравится 0 Проголосовать: не нравится

        Then there's an incomplete information in Wikipedia for IOI

        "The scores from the two competition days and all problems are summed up separately for each contestant. At the awarding ceremony, contestants are awarded medals depending on their relative total score. The top 50% of the contestants are awarded medals, such that the relative number of gold : silver : bronze : no medal is approximately 1:2:3:6 (thus 1/12 of the contestants get a gold medal)."

        Would you mind giving me the that Points?

        Then I'll update wrong medal cases in my stats.

        • »
          »
          »
          »
          »
          10 лет назад, # ^ |
            Проголосовать: нравится 0 Проголосовать: не нравится

          The correct IOI results can be found here.

        • »
          »
          »
          »
          »
          10 лет назад, # ^ |
          Rev. 2   Проголосовать: нравится +1 Проголосовать: не нравится

          The keyword is "approximately". The reason that didn't happen this year is because there were many people with the same amount of points on the gold boundary, and as a result, too many gold medals. Next, the regulations are stated in the way I mentioned previously, and not "the score necessary to achieve a silver medal is the largest score such that at least one fourth of all contestants receive a gold or a silver medal", which many people believe (including myself until 5 days ago) — supported by fact that in 2011 and some previous years the proposal from SC, which ended up as a final medal distribution, was apparently calculated using that non-existent rule rather than what was written in the regulations). This year (or in one of the previous years, as two distributions gave the same outcome in 2012 and 2013) this issue reached SC, and this is why there are extra silver medals as well, if we consider the proportion. Finally, note the difference that the bronze cutoff definition contains "at most" and not "at least". Since we also have people with the same amount of points halfway through the table, we have less than the half of contestants getting the medals as well.

          The cutoffs themselves can be clearly seen in the results. I also have the summary of cutoffs on the main olympiad page.

          To be completely clear, those cutoffs are a little bit modified in a way that doesn't change medal distribution: namely, I have the last medal's score as a cutoff, so I have a bronze cutoff of 223, where the regulations would give a cutoff 222. This doesn't affect anything, but in my opinion is a more useful cutoff. Imagine the first silver has X points, when the last gold has Y. The cutoff of Y says, that to get a gold medal, one would need to score Y points (doesn't work for bronze medals though). The cutoff of X+1 doesn't give this information as the cutoff might just increase to X+2 if someone got X+1 points.

          • »
            »
            »
            »
            »
            »
            10 лет назад, # ^ |
              Проголосовать: нравится 0 Проголосовать: не нравится

            I was astonished about the medal allocation procedure this year. So the IOI 2012 rules also describe the wrong procedure?

            IOI 2012 Competetion Rules

            I couldn't find anything about medal allocation in the IOI 2013 and 2014 rules, and I thought that the 2012 information would be correct.

            • »
              »
              »
              »
              »
              »
              »
              10 лет назад, # ^ |
                Проголосовать: нравится 0 Проголосовать: не нравится

              Hmm, I forgot the allocation algorithm existed in the rules as well. Now it all makes sense to me.

              Looks like everything was OK. The clause determining the default proposal from GA (1/6 for S) according to regulation existed from 2006. Let's skip 2006 due to what happened with results there. In 2007 it was used. However it is only a default proposal, and in 2008 — 2012 it was overridden in rules with specific algorithm (1/4 for G+S) and so it was used. When the rules were shortened in 2013, the overriding medal allocation algorithm was removed as well (would be interesting to know whether deliberately or accidentally), so everything fell back to regulations (which unlike specific IOI rules are still valid next year). It didn't affect 2013, but was rightfully used this year.

»
10 лет назад, # |
  Проголосовать: нравится +12 Проголосовать: не нравится

Have I missed something and Australia already became an algorithm's power or is it just some kind of a fluke, combination of exceptional contestant and luck on contest? Note that Australia is the only country, which got 2 perfect scores on 2nd day, which was in my opinion very hard! Congratulations on very good performance!

  • »
    »
    10 лет назад, # ^ |
      Проголосовать: нравится 0 Проголосовать: не нравится

    I think it's a combinational of very good problem solving skills and being in the right mindset. Friends is the typical high variance IOI problem (there is a 30 line solution, and you can easily write over 100 lines by overcomplicating things).

    The only two countries with two full scores on Friends are China and Australia, and the Aussies have 1 more full score on Holiday as well, so their day 2 performance is quite spectacular.

  • »
    »
    10 лет назад, # ^ |
      Проголосовать: нравится +21 Проголосовать: не нравится

    It is definitely a case of stars the aligning for us to have 4 very good competitors in 1 year, this year will be a peak at least for a few years to come.

    However it is also a result of an excellent training program, and hard work by both students and tutors. We have 2 10-day camps throughout the year, as well as a 5 day camp just before IOI, all of which are very well run. So sure there was some luck, but I do think that this sort of result wasn't outside of our realistic hopes.

    As a side note, you can't judge the Australian team by CF rating as the usual CF round time is 1:30AM, or 2:30 depending on daylight savings.