[R] WRS2 package problems with post hoc test lincon

[David Winsemius]

> On Jul 7, 2016, at 5:43 PM, lhartman at yorku.ca wrote:
> 
> 
> 
> 	Hello,
> 
> 	I am analyzing some data that has violated assumptions of ANOVA

Violated? Violated how exactly?


> and am
> using the WRS2 package in R.


Where's the code?


> 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)  

CR's and minor editing added.

> Schizophrenia Schizoaffective Control

> 89.29412      95.83333        95.54545

> 	>
> 	The post hoc test

Test? Test of what (and how)?


> 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,

Did you really intend that sentence to say that?


> 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.

That's the test ( lincon? ) you didn't illustrate with code?


> Thank you.
> 
> 	Best,
> 
> 	Leah Hartman
> 
> 	[[alternative HTML version deleted]]
> 
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David Winsemius
Alameda, CA, USA