[R] WRS2 package problems with post hoc test lincon

[Jeff Newmiller]

1) HTML formatted email does not come through reliably. Please read the Posting Guide. 

2) It is very nearly always necessary to provide a reproducible example when asking for help on this list to avoid complete failure to communicate. 

3) Given the above limitations (meaning I may not be understanding you correctly), this looks like a problem with your understanding of statistics, not a problem with R. If so, you should be asking this question in a forum focused less on the tool and more on the theory, such as stats.stackexchange.com.
-- 
Sent from my phone. Please excuse my brevity.

On July 7, 2016 5:43:58 PM PDT, lhartman at yorku.ca wrote:
>
>
>	Hello,
>
>	I am analyzing some data that has violated assumptions of ANOVA and am
>using the WRS2 package in R. I am comparing three groups, Dx,
>(schizophrenia, schizoaffective and control) on various variables, one
>of
>which is premorbid IQ (preIQ).
>
>	preIQdataSDx  #trimmed means > tapply(preIQdataSPreIQ, preIQdataSDx,
>mean,
>tr=.2, na.rm=TRUE)  Schizophrenia Schizoaffective Control 89.29412
>95.83333
>95.54545
>	>
>	The post hoc test shows that the schizophrenia and controls group
>differ
>significantly which makes sense when you look at their trimmed means;
>however, what does not make sense is that the control and
>schizoaffective
>disorder groups differ significantly from each other (their means are
>almost identical). Additionally, if the schizophrenia and control group
>differ significantly, shouldn't the schizophrenia group also differ
>significantly from the control group too, as the control group and
>schizoaffective disorder groups have very similar means. I am wondering
>if
>the lincon post hoc test is flawed in some way or if I am not setting
>something up correctly in R. Any help is greatly appreciated. Thank
>you.
>
>	Best,
>
>	Leah Hartman
>
>	[[alternative HTML version deleted]]
>
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