[R] Repeated Measures ANOVA and the Bonferroni post hoc test different results of significantly

[peter dalgaard]

> On 24 Jun 2015, at 03:28 , gianni lavaredo <gianni.lavaredo at gmail.com> wrote:
> 
> 
> I am doing an Repeated Measures ANOVA and the Bonferroni post hoc test for
> my data using R project. The ANOVA gives a significantly difference between
> the data but not the  Bonferroni post hoc test.
> 
>> anova(aov2)
>                numDF denDF   F-value p-value
>    (Intercept)     1  1366 110.51125  <.0001
>    time            5  1366   9.84684  <.0001
> 
> while
> 
>> pairwise.t.test(x=table.metric2$value, g=table.metric2$time,
> p.adj="bonf")


And? 

Notice that pairwise.t.test does not take the plot variable into account. It might if you use paired=TRUE, *IF* your data layout allows it (so that when you split the data by times, observations in each subvector are from the same plots in the same order). 

-pd

-- 
Peter Dalgaard, Professor,
Center for Statistics, Copenhagen Business School
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Email: pd.mes at cbs.dk  Priv: PDalgd at gmail.com