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Blast Attenuation Confidence limits 2

Blast Attenuation Confidence limits 2

Blast Attenuation Confidence limits 2

(OP)
This is a follow on to a previous thread which is now closed.

About ten years ago I was working out the confidence limits for scaled distances.

My collection of photocopied published papers  kept from my recent stint back at college contained a number of statistical flaws:

The authors had frequently assumed a "Normal" distribution, this would only be justified when the sample population has 120 or more degrees of freedom (sample size > or equal to 121 measurements). For smaller sample populations a "t" distribution world be required.

Even assuming that a normal population was useable, the authors had also frequently used 1.96*SD as the limit for 95% confidence. This is the limit for a 2 tailled test and describes the central 95%.  Applied to the upper end it is defining 97.5% confidence limit!

I think the main culprit was Wilton & Johnston's 1992 quotation (or mis quotation) of Lucole & Dowding (1979).

Keith

 

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