There is a ttest with adjustment for clustering by Jeph Herrin on SSC,
would this be what you are lookingfor?
cltest is a pair of programs for analyzing data that have been
randomized in clusters. clttest compares the means of two sets
of grouped outcomes, with optional support for group-stratified
outcomes. clchi2 estimates an adjusted chi-square test of
independence for 2xk groups, with optional support for
group-stratified outcomes. Adjustments for clustering are taken
from Donner & Klar (Cluster Randomization Trials in Health
Services Research, 2000), with the CLCHI2 program generalized to
the 2xk case. chchi2 uses loneway to calculate the inter-cluster
correlation, which in Stata 6.0 and higher includes a correction
for imbalanced groups.
Distribution-Date: 20021204
Author: Jeph Herrin
Support: email [email protected]
Buzz Burhans
[email protected]
>> In the original line-up, the coefficient of determination is
>> 0.968. In the
>> second one above, its 0.8.
>>
>>
>> -----Original Message-----
>> From: Scott Merryman [mailto:[email protected]]
>> Sent: Monday, May 10, 2004 6:42 PM
>> To: [email protected]
>> Subject: st: RE: unpaired regression
>>
>> How about lining up the measurements?
>>
>> Something like
>>
>> . l
>>
>> +-------------------------+
>> | batch assay1 assay2 |
>> |-------------------------|
>> 1. | Btch1 5400 . |
>> 2. | Btch1 5320 . |
>> 3. | Btch1 5670 . |
>> 4. | Btch1 . .9 |
>> 5. | Btch1 . .905 |
>> |-------------------------|
>> 6. | Btch1 . .898 |
>> 7. | Btch2 8600 . |
>> 8. | Btch2 7840 . |
>> 9. | Btch2 7550 . |
>> 10. | Btch2 . .962 |
>> |-------------------------|
>> 11. | Btch2 . .955 |
>> 12. | Btch2 . .943 |
>> +-------------------------+
>>
>> . by batch: replace assay2 = assay2[_n +3]
>> (12 real changes made, 6 to missing)
>>
>> . drop if assay1 == .
>> (6 observations deleted)
>>
>> . l
>>
>> +-------------------------+
>> | batch assay1 assay2 |
>> |-------------------------|
>> 1. | Btch1 5400 .9 |
>> 2. | Btch1 5320 .905 |
>> 3. | Btch1 5670 .898 |
>> 4. | Btch2 8600 .962 |
>> 5. | Btch2 7840 .955 |
>> |-------------------------|
>> 6. | Btch2 7550 .943 |
>> +-------------------------+
>>
>>
>> Scott
>>
>> ________________________________________
>> From: [email protected]
>> [mailto:[email protected]] On Behalf Of
>> Wallace, John
>> Sent: Monday, May 10, 2004 7:48 PM
>> To: '[email protected]'
>> Subject: st: unpaired regression
>>
>> I have two measures of batch performance on which I'd like to
>> perform a
>> regression. The measurements are taken on separate samples
>> from the batch,
>> and typically look something like:
>> Assay1 Assay2
>> Btch1 5400
>> Btch1 5320
>> Btch1 5670
>> Btch1 0.900
>> Btch1 0.905
>> Btch1 0.898
>> Btch2 8600
>> Btch2 7840
>> Btch2 7550
>> Btch2 0.962
>> Btch2 0.955
>> Btch2 0.943
>> ...etc (on for multiple batches which show correlated
>> measures for the two
>> assays)
>> -collapse- ing them to batch averages and then performing the
>> regression is
>> one approach, but it doesn't take variance of the measures
>> themselves into
>> account in the regression. Is there a system for performing
>> this type of
>> analysis?
>>
>
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> *
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> * http://www.ats.ucla.edu/stat/stata/
>
*
* For searches and help try:
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