# Find accept rate

I'm a bit stacked with finding accept rate.
Let's say I want to deposit some notes by using ATM and here's what I got:

1st attempt: 3 notes from 4 were validated, means accept rate is 75%
2nd attempt: 0 notes from 1 were validated, means accept rate is 0%
3rd attempt: 1 note  from 1 was  validated, means accept rate is 100%


I will appreciate if someone explain me how to find real accept rate, based on this experiment?

UPDATE To make it more clear: I'm working on some hardware which is charge of notes recognition. To verify that recognition algorithm is suitable and efficient I need to calculate accept rate, so I'm making recognition attempts and write down results to calculate this rate later.

1st option to calculate accept rate is:
(75% + 0% + 100%) / 3 = 58.3%
2nd option is:
(3 + 0 + 1)/(4+1+1) = 4/6 = 2/3 = 66.7%


And the question is how to calculate this right

• Suppose the data were 0 validated out of 4 on the first attempt (0%), 0 validated out of 1 on the second attempt (0%), and 995 validated out of 995 on the third attempt (100%). Do you think (0+0+100)/3 = 33.3% would be an appropriate summary of the results?
– whuber
Oct 30, 2017 at 14:11

## 1 Answer

You just add up the numbers and divide. (3 + 0 + 1)/(4 + 1 + 1) = 4/6 = 2/3.

• Your recommendation is unclear: harmonic mean of what numbers, exactly? Note that the harmonic mean of 75%, 0%, and 100% is undefined. And what assumptions underlie (and therefore would justify) adding up the numbers as you describe?
– whuber
Oct 28, 2017 at 13:23