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Message: <blockquote data-quote="Arkhandus" data-source="post: 3814800" data-attributes="member: 13966">Most likely, time isn't the only thing used to determine the 'random' numbers, and anyway, the computer's probably measuring passage of time in nanoseconds or milliseconds, so the time variable used in the calculation would still be changing rapidly.This is mentioned in the Hero Builder's Guidebook, one of the old 3.0 thin softcover books by Wizards of the Coast (meant for newbies, but I thought it was handy enough for generating names and character ideas, which it is).  It explains the difference in probability from the 3rd Edition standard of 4d6-drop-lowest for ability scores, compared to the old standard of just 3d6.I could do the math myself, but I hate doing probability calculations and making sure I got the equation set up right.  So I'll just tell ya what the book says.  In the old method of 3d6 for ability scores, there was a roughly 0.5% chance of rolling a score of 18 (based on a supposed set of 200 rolls of 3d6, only 1 could be expected to be an 18 under the laws of probability).  Roughly 3% of characters using that method could be expected to have a single 18 among their ability scores.  The average value of each ability score would be 10.5 (in other words, an even mix of 10s and 11s among the scores).In the 3E method of 4d6-drop-lowest, rolling the extra die and discarding the lowest of the four means you're adding another chance for a good roll into the mix, simply through the law of averages.  Even though that extra die still has only a 1-in-6 chance of rolling any particular result (like a 6).  I'm no expert in the laws of probability and the law of averages, so I won't bother trying to coherently explain the reasoning, but basically, when you look at a larger number of instances of a particular event, the likelyhood that their results will average out increases, because across a larger sampling, the law of averages has a greater probability of showing through in the outcome.The 4d6-drop-lowest method produces an average ability score of 11.5, because the extra die roll produces a steeper bell curve of results according to probability.....so the 'middle ground', the peak of the bell curve, is broader and you're more likely to achieve an average result out of that sampling.  It's the drop-lowest part that produces this slightly more favorable 'average'; if the method was drop-highest, it would be the reverse, and if it was drop-the-roll-closest-to-3-or-4 or somesuch, then it would probably produce much the same 'average' as the 3d6 method.With the slightly more favorable set-up of 4d6-drop-lowest, your odds of rolling one score of 18 among your set of six abilities is roughly 9%, rather than 3%.  Also because of the slightly-favorable nature of the drop-lowest part, your odds of rolling a really low score are diminished.</blockquote>

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