Normal Probablility plot

HemaB — Wed, 06 May 2015 12:38:30 GMT

Hi All,

Could you let me know if anyone avire of this concept.

in my study i have a requirement for probability plot the query is like this --> "Normal probability plot with simulation envelope from the mixed model" means i should i do?

1) is it from raw data or

2) should i consider anything from mixed model results?

thanks in advance.

Hima B

Re: Normal Probablility plot

Rick_SAS — Tue, 19 May 2015 18:08:22 GMT

Normal probability plot of what? The residuals?

Many SAS procedures produce normal quantile-quantile plots automatically. The Q-Q plot is very similar to the probability plot, but the Q-Q plot is usually easier to read than the probability plot, and makes deviations from normality more apparent.

A "envelope" usually means that you run an analysis many times and look at the 2.5% and 97.5% percentiles of the results. For a Q-Q plot, you might bootstrap the data and store the data for 1000 Q-Q plots. You then plot the appropriate percentiles as the envelope.

I do not know what the term "simulation envelope from the mixed model" means. Perhaps someone else might be able to provide insight.

topic Normal Probablility plot in Statistical Procedures

Normal Probablility plot

Re: Normal Probablility plot