For the overall average you need is the total time and total characters. Do the division at presentation time.
If you want a decaying moving average, then a variant on Welford's method is useful for an on-line estimate. I just had such a discussion in the hbase group. For that you need state, however, and atomic updates. A useful approximation might be possible if you can report many moving averages which can themselves be averaged. Can you say a bit more about your context? Is this in hadoop? Did you want to maintain the average across the cluster? Did you want real averages or a moving average? Do you have constant sampling rate? On Mon, Mar 14, 2011 at 7:33 AM, Benson Margulies <[email protected]>wrote: > Please excuse the following ignorant question. > > I want to maintain summary statistics of a rate. At each 'event', I > know the number of characters and the time it took to process them, > and I want to maintain summary statistics for the rate of > chars/second. I imagine that I'm missing something basic, but I don't > see how to do this. > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [email protected] > For additional commands, e-mail: [email protected] > >
