Just trying to compute least square means for a repeated measures ANOVA!

[Jaime Devine]

I can't get adjusted means for both treatment conditions (drug and placebo) across three time points. Margins will give me estimation for the time points, but not by condition. Syntax is:

anova *IV* drugcondition/subjid|drugcondition timepoint drugcondition#timepoint c.*covariate*, repeated(timepoint)

I tried adjust xi regress, and margins, and even separating the data to create separate drug and placebo files to try to generate timepoint margins. I could get adjusted margins for placebo but not the drug condition in that case.

What am I doing wrong? Is there a way to manually calculate least square means from unadjusted means?

[Joseph Coveney]

I can't get adjusted means for both treatment conditions (drug and placebo) across three time points. Margins will give me estimation for the time points, but not by condition. . . . What am I doing wrong?

Use the -noestimcheck- option. See below.

Begin at the "Begin here" comment; the first part of the output shows just generation of a fictitious toy dataset for illustration, one that has characteristics yours has.

.ÿ
.ÿversionÿ16.0

.ÿ
.ÿclearÿ*

.ÿ
.ÿsetÿseedÿ`=strreverse("1529824")'

.ÿ
.ÿquietlyÿsetÿobsÿ20

.ÿgenerateÿbyteÿpidÿ=ÿ_n

.ÿgenerateÿdoubleÿpid_uÿ=ÿrnormal()

.ÿgenerateÿbyteÿtrtÿ=ÿmod(_n,ÿ2)

.ÿ
.ÿquietlyÿexpandÿ3

.ÿbysortÿpid:ÿgenerateÿbyteÿtimÿ=ÿ_n

.ÿgenerateÿdoubleÿcvtÿ=ÿruniform()ÿ-ÿ0.5

.ÿ
.ÿgenerateÿdoubleÿoutÿ=ÿpid_uÿ+ÿrnormal()

.ÿ
.ÿ*
.ÿ*ÿBeginÿhere
.ÿ*
.ÿanovaÿoutÿtrtÿ/ÿpid|trtÿtimÿtrt#timÿc.cvt,ÿrepeated(tim)

ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿNumberÿofÿobsÿ=ÿÿÿÿÿÿÿÿÿ60ÿÿÿÿR-squaredÿÿÿÿÿ=ÿÿ0.7516
ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿRootÿMSEÿÿÿÿÿÿ=ÿÿÿÿ.882956ÿÿÿÿAdjÿR-squaredÿ=ÿÿ0.5812

ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿSourceÿ|ÿPartialÿSSÿÿÿÿÿÿÿÿÿdfÿÿÿÿÿÿÿÿÿMSÿÿÿÿÿÿÿÿFÿÿÿÿProb>F
ÿÿÿÿÿÿÿÿÿÿÿÿÿÿ-----------+----------------------------------------------------
ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿModelÿ|ÿÿ82.550903ÿÿÿÿÿÿÿÿÿ24ÿÿÿÿ3.439621ÿÿÿÿÿÿ4.41ÿÿ0.0000
ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ|
ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿtrtÿ|ÿÿ1.5187152ÿÿÿÿÿÿÿÿÿÿ1ÿÿÿ1.5187152ÿÿÿÿÿÿ0.37ÿÿ0.5529
ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿpid|trtÿ|ÿÿ74.749044ÿÿÿÿÿÿÿÿÿ18ÿÿÿ4.1527246ÿÿ
ÿÿÿÿÿÿÿÿÿÿÿÿÿÿ-----------+----------------------------------------------------
ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿtimÿ|ÿÿ.69660425ÿÿÿÿÿÿÿÿÿÿ2ÿÿÿ.34830212ÿÿÿÿÿÿ0.45ÿÿ0.6433
ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿtrt#timÿ|ÿÿ.97316917ÿÿÿÿÿÿÿÿÿÿ2ÿÿÿ.48658458ÿÿÿÿÿÿ0.62ÿÿ0.5416
ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿcvtÿ|ÿÿ2.5437328ÿÿÿÿÿÿÿÿÿÿ1ÿÿÿ2.5437328ÿÿÿÿÿÿ3.26ÿÿ0.0795
ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ|
ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿResidualÿ|ÿÿ27.286417ÿÿÿÿÿÿÿÿÿ35ÿÿÿ.77961191ÿÿ
ÿÿÿÿÿÿÿÿÿÿÿÿÿÿ-----------+----------------------------------------------------
ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿTotalÿ|ÿÿ109.83732ÿÿÿÿÿÿÿÿÿ59ÿÿÿ1.8616495ÿÿ


Between-subjectsÿerrorÿterm:ÿÿpid|trt
ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿLevels:ÿÿ20ÿÿÿÿÿÿÿÿ(18ÿdf)
ÿÿÿÿÿLowestÿb.s.e.ÿvariable:ÿÿpid
ÿÿÿÿÿCovarianceÿpooledÿover:ÿÿtrtÿÿÿÿÿÿÿ(forÿrepeatedÿvariable)

Repeatedÿvariable:ÿtim
ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿHuynh-Feldtÿepsilonÿÿÿÿÿÿÿÿ=ÿÿ1.1569
ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ*Huynh-Feldtÿepsilonÿresetÿtoÿ1.0000
ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿGreenhouse-Geisserÿepsilonÿ=ÿÿ0.9780
ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿBox'sÿconservativeÿepsilonÿ=ÿÿ0.5000

ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ------------ÿProbÿ>ÿFÿ------------
ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿSourceÿ|ÿÿÿÿÿdfÿÿÿÿÿÿFÿÿÿÿRegularÿÿÿÿH-FÿÿÿÿÿÿG-GÿÿÿÿÿÿBox
ÿÿÿÿÿÿÿÿÿÿÿÿÿÿ-----------+----------------------------------------------------
ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿtimÿ|ÿÿÿÿÿÿ2ÿÿÿÿÿ0.45ÿÿÿ0.6433ÿÿÿ0.6433ÿÿÿ0.6391ÿÿÿ0.5126
ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿtrt#timÿ|ÿÿÿÿÿÿ2ÿÿÿÿÿ0.62ÿÿÿ0.5416ÿÿÿ0.5416ÿÿÿ0.5383ÿÿÿ0.4401
ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿResidualÿ|ÿÿÿÿÿ35
ÿÿÿÿÿÿÿÿÿÿÿÿÿÿ----------------------------------------------------------------

.ÿ
.ÿmarginsÿtrtÿtimÿtrt#tim,ÿnoestimcheckÿ//ÿ<=ÿthis

PredictiveÿmarginsÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿNumberÿofÿobsÿÿÿÿÿ=ÿÿÿÿÿÿÿÿÿ60

Expressionÿÿÿ:ÿLinearÿprediction,ÿpredict()

------------------------------------------------------------------------------
ÿÿÿÿÿÿÿÿÿÿÿÿÿ|ÿÿÿÿÿÿÿÿÿÿÿÿDelta-method
ÿÿÿÿÿÿÿÿÿÿÿÿÿ|ÿÿÿÿÿMarginÿÿÿStd.ÿErr.ÿÿÿÿÿÿtÿÿÿÿP>|t|ÿÿÿÿÿ[95%ÿConf.ÿInterval]
-------------+----------------------------------------------------------------
ÿÿÿÿÿÿÿÿÿtrtÿ|
ÿÿÿÿÿÿÿÿÿÿ0ÿÿ|ÿÿÿ.3548227ÿÿÿ.2910456ÿÿÿÿÿ1.22ÿÿÿ0.231ÿÿÿÿ-.2360313ÿÿÿÿ.9456767
ÿÿÿÿÿÿÿÿÿÿ1ÿÿ|ÿÿÿ.2443729ÿÿÿ.2911299ÿÿÿÿÿ0.84ÿÿÿ0.407ÿÿÿÿ-.3466521ÿÿÿÿ.8353979
ÿÿÿÿÿÿÿÿÿÿÿÿÿ|
ÿÿÿÿÿÿÿÿÿtimÿ|
ÿÿÿÿÿÿÿÿÿÿ1ÿÿ|ÿÿ-.0554601ÿÿÿÿ.197471ÿÿÿÿ-0.28ÿÿÿ0.780ÿÿÿÿ-.4563475ÿÿÿÿ.3454274
ÿÿÿÿÿÿÿÿÿÿ2ÿÿ|ÿÿÿÿÿ.16037ÿÿÿ.1979315ÿÿÿÿÿ0.81ÿÿÿ0.423ÿÿÿÿ-.2414523ÿÿÿÿ.5621922
ÿÿÿÿÿÿÿÿÿÿ3ÿÿ|ÿÿÿ.1840635ÿÿÿ.1977005ÿÿÿÿÿ0.93ÿÿÿ0.358ÿÿÿÿ-.2172898ÿÿÿÿ.5854167
ÿÿÿÿÿÿÿÿÿÿÿÿÿ|
ÿÿÿÿÿtrt#timÿ|
ÿÿÿÿÿÿÿÿ0ÿ1ÿÿ|ÿÿÿ.0348159ÿÿÿ.3696835ÿÿÿÿÿ0.09ÿÿÿ0.926ÿÿÿÿ-.7156815ÿÿÿÿ.7853134
ÿÿÿÿÿÿÿÿ0ÿ2ÿÿ|ÿÿÿ.5587044ÿÿÿ.3694006ÿÿÿÿÿ1.51ÿÿÿ0.139ÿÿÿÿ-.1912187ÿÿÿÿ1.308628
ÿÿÿÿÿÿÿÿ0ÿ3ÿÿ|ÿÿÿ.4709478ÿÿÿ.3712234ÿÿÿÿÿ1.27ÿÿÿ0.213ÿÿÿÿ-.2826757ÿÿÿÿ1.224571
ÿÿÿÿÿÿÿÿ1ÿ1ÿÿ|ÿÿÿ.2608106ÿÿÿ.3702343ÿÿÿÿÿ0.70ÿÿÿ0.486ÿÿÿÿ-.4908051ÿÿÿÿ1.012426
ÿÿÿÿÿÿÿÿ1ÿ2ÿÿ|ÿÿÿ.1685822ÿÿÿ.3695034ÿÿÿÿÿ0.46ÿÿÿ0.651ÿÿÿÿ-.5815495ÿÿÿÿÿ.918714
ÿÿÿÿÿÿÿÿ1ÿ3ÿÿ|ÿÿÿ.3037258ÿÿÿ.3697348ÿÿÿÿÿ0.82ÿÿÿ0.417ÿÿÿÿ-.4468757ÿÿÿÿ1.054327
------------------------------------------------------------------------------

.ÿ
.ÿexit

endÿofÿdo-file


.

[Jaime Devine]

Thank you so much! You made that ridiculously easy.