- #1
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Why are so many phenomena well described by the normal distribution?
For example: the height of 18 year old males in Sweden, the weight of apples on a particular tree, the volume of coke cans (supposed to be 33 cl), etc. etc. are all well described by the normal distribution.
How come?
A typical answer would be to refer to the Central Limit Theorem (CLT). In its standard formulation, CLT says that the distribution of the (normalized) average of n indepedent, identically distributed stochastic variables approaches the standard normal distribution as n → ∞.
Although there are several versions of CLT for which the assumptions are weakened, I still don't see how it can be applied to the cases above. Since these don't deal with averages, how can CLT in any form be applied?
For example: the height of 18 year old males in Sweden, the weight of apples on a particular tree, the volume of coke cans (supposed to be 33 cl), etc. etc. are all well described by the normal distribution.
How come?
A typical answer would be to refer to the Central Limit Theorem (CLT). In its standard formulation, CLT says that the distribution of the (normalized) average of n indepedent, identically distributed stochastic variables approaches the standard normal distribution as n → ∞.
Although there are several versions of CLT for which the assumptions are weakened, I still don't see how it can be applied to the cases above. Since these don't deal with averages, how can CLT in any form be applied?