Determine Valid Sample Size from a Population - Any UDFs or Formulas?
 

No question here, just a function for the archive.

For what it's worth, here's a quick function for getting a "quick"
estimate for a valid sample size based on the assumptions below.


Function SampleSizeQuickAt95PercentCL(ConfidenceInterval As Double,
Population As Double) As Long
'Calculates a "quick" necessary sample size from a Finite Population
'based on these assumptions:
'1. Normal Distribution
'2. Confidence Level = 95%
'3. Response Rate = 50%
'References: http://www.surveysystem.com/sscalc.htm

Dim SampleSize As Long
Dim CorrectionForFinitePopulation As Long

On Error Resume Next
SampleSize = ((1.96 * 2) * 0.5 * (1 - 0.5)) / (ConfidenceInterval
* ConfidenceInterval)
CorrectionForFinitePopulation = SampleSize / (1 + ((SampleSize -
1) / Population))

SampleSizeQuickAt95PercentCL = CorrectionForFinitePopulation

End Function