radicallyopensecurity / PassiveScanningTool

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Sample size calculation may be incorrect #8

Open boisletterink opened 8 years ago

boisletterink commented 8 years ago

When asked for an explanation of the sample size, Koen explained the following:

[15:26:57] Koen J: https://www.ltcconline.net/greenl/courses/201/estimation/ciprop.htm [15:27:15] Koen J: I guess that summarizes the math somehow, still starts with the formula that comes from estimation theory [15:27:24] Koen J: let me link the exact formula that we're interested in [15:27:39] Koen J: https://www.ltcconline.net/greenl/images/NumInts/img8.gif [15:27:41] Koen J: that's the one [15:28:32] Koen J: p = deviation (typically 50%) [15:28:36] Koen J: e = margin of error (typically 5%) [15:28:45] Koen J: z = 1.96

This does not conform to the calculation in CalculateSampleSize() in Utilities.cs.

Which one is correct?