I am measuring time of a computer operation. The operation should run roughly same time each time I measure it. How many times should I measure it to get good average and standard deviation?
closed as off topic by David Z♦ May 17 '13 at 23:14
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It depends a lot on the precision that you want to achieve on your measurement. As standard, it is considered that with 10 times that you run the operation it should be enough. But to know clearly the times that you need to run the operation, just check the standard deviation. With a few times, say 5, it is large but it goes down as you add more runs to the statistics. You should be able to observe the decrease on the value of the standard deviation every 5 times you run the calculation.