confidence interval for lognormal distribution

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confidence interval for lognormal distribution

jimjohn
hi guys, just a quick question. if i want a confidence itnerval for a lognormally distributed variable, can i still use the standard normal distribution table to calculate my critical values. or are the critical values different for lognormals than for normals? thanks!
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Re: confidence interval for lognormal distribution

Marta Garcia-Granero
jimjohn wrote:
> hi guys, just a quick question. if i want a confidence itnerval for a
> lognormally distributed variable, can i still use the standard normal
> distribution table to calculate my critical values. or are the critical
> values different for lognormals than for normals? thanks!
>

Compute the CI with the log transformed data, and then back-transform
the limits. Remember that you will have then a CI for the geometric
mean, not the arithmetic mean.

Marta GG


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