January 21, 2012 Mike Bostock Or, why random comparators are bad (in addition to being slow). This matrix diagram visualizes the probability of each element i being placed in position j at the end of a random shuffle. Red cells represent negative bias ; green cells represent positive bias . A good shuffling algorithm is unbiased ; you should see a uniform grey matrix with only a bit of white noise. A bad algorithm will show streaks in the matrix, indicating an un­even distribution. For more details, read my previous post on the Fisher–Yates shuffle . Also see screenshots of different browsers . Built with d3.js . Choose an algorithm: Or write your own: refresh auto-refresh Comments? Discuss on HN! January 21, 2012 Mike Bostock ...