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svenhof
2650 days ago
Unfortunately, by averaging the averages you skew the results. Average of averages does not produce the same result as averaging the whole list.
3 comments
sokoloff
2650 days ago
Average of equal size chunks' averages does. (mathematically)
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svenhof
2650 days ago
Ah my bad. Thanks for that correction
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BubRoss
2650 days ago
It does if you weight the chunks correctly. Combine pairs of numbers and keep a weight of the remaining odd number. Either cut the weight in half of the odd number every time or use it in the average if an iteration has an even number of numbers.
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svenhof
2650 days ago
Thanks for that, didn't know.
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umdiff
2650 days ago
\left( \sum_{i=1}^m x_i/m + \sum_{i=m+1}^{2m} x_i/m \right) / 2 = \sum_{i=1}^{2m} x_i /(2m)
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