Elo rating system for chess, facemash, The Social Network скачать в хорошем качестве

Elo rating system for chess, facemash, The Social Network

Actual clip of the formula written on Mark's dorm window. http://www.cinemablend.com/new/You-ll... Those who saw the movie "The Social Network" remember the beginning of the story, Mark Z asked his friend to come help him with the development of facemash.com while drunk. Facemash was designed to rank girls, one against another. Why should we need a formula? Because in the real world, we simply cannot have time for every voter (judge) to compare each player against another. For just 10 competitors, you'd need to compete 9+8+7+6+5+4+3+2+1= 45 times. Shortcut to solving this addition problem is Gauss' pairwise method = 9+8+7+6+5+4+3+2+1 = (9+1)+(2+8)+(3+7)....+ 5 = 45 So imagine, if you had 100 players, or 1000 players. No real world race would be based on giving every new player a chance to compete with all others, nor would it be fair to make the established winners prove themselves each time, so this formula records one's history, and works from there. With much less information, and gets a faster result. Chess rating systems http://en.wikipedia.org/wiki/Elo_rati... http://en.wikipedia.org/wiki/Chess_ra... Hot Or Not employs Condorcet Method http://en.wikipedia.org/wiki/Condorce... In sports, we have a "Seeding" method http://en.wikipedia.org/wiki/Seed_%28... Playoffs use a bracket/branching method http://en.wikipedia.org/wiki/Single-e... In simple logic, if you were told B wins L L wins M You wouldn't waste time asking if B wins M Because assuming the above 2 comparisons are true, you can conclude B wins L, which in turn wins M. This is the kind of work and time formulas are designed to reduce, while focusing on actual disagreements amongst voters. EDIT ADD : I apologize that this wasn't emphasized in the video, the REAL BENEFIT comes in, when a new player in introduced, and in a big population, all new uncontested players are "new". When you have limited amounts of competitions, you need to think strategically how to schedule your opponents, that's what makes ranking more accurate, and this formula more useful.