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AndersBergquist
Quartz | Level 8
I have a question about the estimation about confidence limits and proc surveymeans.

When we estimates the confidence limits, it seams that SAS does not take the df in account? It makes just a point estimate with SD * 2.04.

Is this the correct behavior? or is there a way to make SAS adjust the 2.04 coefficint according to the df and the numbers in the t-tables?
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lvm
Rhodochrosite | Level 12 lvm
Rhodochrosite | Level 12
SURVEYMEANS does take df into account. The df calculation depends on whether you have clusters and/or strata. In the simplest case, with no clusters or strata (which means that each observation is a cluster), df = number of observations - 1. For your example, 2.04 IS the critical t value (with alpha=.05). By the way, CI is SE*t (not SD*t).

You can see the calculated df value by putting df in the procedure statement.

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