An asymmetric distribution is a probability distrubution that is asymetric about its median. For example, waiting times in many contexts are often highly asymetric, not least because ther cannot be negative waiting times, but aso becasue there may also be occasional long waiting times. Asymmetric distributions are often heavily skewed, as in the example of waiting times, with a long tail on one side, but may also simply be different shapes.
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