SAS Results for uncorrected data from exemplar 2

The following warning appears in the log file

NOTE: Writing HTML Body file: sashtm.htm

NOTE: Only one cluster in a stratum for variable(s) intuse. The variance of intuse in that stratum is estimated by zero.

But no warning about PSUs that cross strata

Simple proportion internet use

The SURVEYMEANS Procedure

Data Summary
Number of Strata	329
Number of Clusters	11941
Number of Observations	28685
Sum of Weights	28702.2953

Stratum Information
Stratum Index	STRATUM	N Obs	Variable	N	Clusters
1	100A	202	INTUSE	202	202
2	100B	130	INTUSE	130	130
81	190G	51	INTUSE	51	4
82	190I	10	INTUSE	10	1
157	250Z	6	INTUSE	6	1
158	260A	229	INTUSE	229	229
159	260B	145	INTUSE	145	145
329	400Z	3	INTUSE	3	1

  Rows omitted to save space

Statistics
Variable	Label	N	Mean	Std Error of Mean	Lower 95% CL for Mean	Upper 95% CL for Mean
INTUSE	Whether person uses the --internet	28685	0.341363	0.003386	0.334725	0.348000