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How to calculate necessary conversions from only sample size and desired statistical significance?

efplotts 03-15-16

How to calculate necessary conversions from only sample size and desired statistical significance?

As the title says, how do I calculate necessary conversions from only sample size and desired statistical significance?

 

For example, if my sample size is 18000 and my statistical significance is 95%, how can I work backward to find a minimum viable conversion rate?

 

Any help is much appreciated!

Level 1

DavidS 03-16-16
 

Re: How to calculate necessary conversions from only sample size and desired statistical significanc

Hi there,

 

Thanks for reaching out!

I understand that you would like to find out the conversion rate you will need to achieve with given statistical significance and sample size numbers. 

 

Unfortunately it is not possible to find directly the conversion rate necessary for a given sample size and a 95% statistical significance. 

 

As an alternative, we have a sample size calculator that you can play with: Sample Size Calculator. Even though it is meant to find out the sample size for a given baseline conversion rate, minimum desirable effect and statistical significance, you can use it to reverse engineer the conversion rate you will need to get with a sample size of 18,000 and a 95% statistical significance. Please keep it mind that this is not what the tool is for in the first place and can't be considered official. 

 

I hope that is helpful. Feel more than free to reply back with any additional questions at all.

 

Best,
David

 

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