Parallel Algorithm
Chan et al. note that the above online algorithm III is a special case of an algorithm that works for any partition of the sample into sets, :
- .
This may be useful when, for example, multiple processing units may be assigned to discrete parts of the input.
Chan's method for estimating the mean is numerically unstable when and both are large, because the numerical error in is not scaled down in the way that it is in the case. In such cases, prefer .
Read more about this topic: Algorithms For Calculating Variance
Famous quotes containing the word parallel:
“There is a parallel between the twos and the tens. Tens are trying to test their abilities again, sizing up and experimenting to discover how to fit in. They don’t mean everything they do and say. They are just testing. . . . Take a good deal of your daughter’s behavior with a grain of salt. Try to handle the really outrageous as matter-of-factly as you would a mistake in grammar or spelling.”
—Stella Chess (20th century)