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# Interpreting/translating glimmix output into a formula for use in Excel or other programs

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I have a data set which displays a "lognormal" shaped dependence of Y on X. The data is radioactive emission rate as a function of time. I see a rapid rise in the early stages followed by a slower decay over time.

The code I use is as follows:

proc glimmix data = QUERY_FOR_SUB1CT;

model rate = time / dist=lognormal link=log noscale solution;

run;

I found this code in an example in the communities. My question is how do I translate the results into a function that I can use in another program such as Excel. My parameter estimates are:

 Parameter Estimates Effect Estimate StandardError DF t Value Pr > |t| Intercept -17.2289 65.7665 29249 -0.26 0.7933 time -0.00013 0 29249 -Infty <.0001 Scale 11.9519 0.09883 . . .

I see on Wikipedia that the lognormal pdf is as attached in the pic but I fail to see how to populate this equation given the SAS output.

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‎11-16-2017 10:30 AM
SAS Super FREQ
Posts: 4,172

## Re: Interpreting/translating glimmix output into a formula for use in Excel or other programs

Are you sure that you want to use LINK=LOG?

To model lognormal data, most people use only DIST=LOGNORMAL and an identity link function.The assumption is that

LOG(rate) is normally distributed and is estimated by

LOG(RATE) = -17.23 - 0.00013*Time + eps

where eps (the residuals) is normally distributed with a variance that is estimated by the scale parameter.

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Solution
‎11-16-2017 10:30 AM
SAS Super FREQ
Posts: 4,172

## Re: Interpreting/translating glimmix output into a formula for use in Excel or other programs

Are you sure that you want to use LINK=LOG?

To model lognormal data, most people use only DIST=LOGNORMAL and an identity link function.The assumption is that

LOG(rate) is normally distributed and is estimated by

LOG(RATE) = -17.23 - 0.00013*Time + eps

where eps (the residuals) is normally distributed with a variance that is estimated by the scale parameter.

New Contributor
Posts: 2

## Re: Interpreting/translating glimmix output into a formula for use in Excel or other programs

You are correct. I forgot to alter my code in what I posted above. On my machine I am using an identity link, such that results appear as follows.

 Parameter Estimates Effect Estimate StandardError DF t Value Pr > |t| Intercept -2.7970 0.01497 29249 -186.85 <.0001 time -0.00124 0.000120 29249 -10.28 <.0001 Scale 3.5190 0.02910 . . .
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