How to Transform Non-Normal Statistical Data to Normal and Back Again using Minitab

When performing statistical analysis on data that is not normally distributed, I often need to transform the data into a normal distribution. This can be done easily with Minitab using the Johnson Transformation, however, the summary statistics output (e.g. mean and confidence interval) is in the transformed scale. I need to transform the output back into the original scale. This can be done by obtaining the transformation function from Minitab, and solving the inverse of the function using Wolfram Alpha. Essentially, we are transforming the data, and reverse-transforming the summary statistics on the data.

You can find more information about transforming non-normal data in the Minitab Blog.

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