Mr. Twister

Этот заход не понял -- The chance of a random guess being correct in our dataset around 43% when guessing browser, and 42% when guessing operating system, so these are the numbers to beat; the reason these numbers are so high is because some browsers and operating systems appear far more in our dataset. We calculated these random guess accuracies by doing simulated random guessing 10,000,000 times and keeping a tally of how often guesses were correct. To simulate random guessing we essentially did two simulated spins of a roulette wheel, where each slice of the wheel represented a browser family or operating system and the slice's size was based on how many times they occurred; if the two spins landed on the same slice then the guess was correct, otherwise it was wrong. To address possible anomalous results we repeated the simulated random guessing several times with different random number generator seeds to ensure that the results were consistent. Please note that this is just the chance of random guessing within our dataset, other datasets may have different distributions of browsers and operating systems, leading to different random guess accuracy.

Это и есть самый простой и точный способ найти вероятность правильного ответа при случайном угадывании над данным фиксированным множеством?