[R] Using influence plots and obtaining id numbers

[Pam]

I am a novice R user, and I am having difficulty understanding R's influence
plots. 

I am trying to remove outliers from a particular variable, "sib." I am able
to generate influence plots and further outlier information such as below
(which is a shortened example). For my analyses, I end up excluding the
points R refers to, 7, 18, 26, and 105. However, my question is, how can I
understand which ID numbers these points (7,18,26, and 105) are referring
to? These numbers, 7,18, 26. and 105, are definitely not my study ID
numbers.


> Myoutput<-aov(sib~newgroup1, data=Study1)
> influencePlot(Myoutput) 
[1]   7  18  26 105
> influence.measures(Myoutput)
Influence measures of
	 aov(formula = sib ~ newgroup1, data = Study1) :

       dfb.1_  dfb.nw12  dfb.nw13  dfb.nw14  dfb.nw15     dffit cov.r  
cook.d    hat inf
33   1.70e-01 -1.33e-01 -1.53e-01 -1.56e-01 -1.52e-01  0.170405 1.124
5.83e-03 0.0909   *
34   7.79e-02 -6.07e-02 -7.00e-02 -7.14e-02 -6.94e-02  0.077934 1.131
1.22e-03 0.0909   *
35   1.47e-01 -1.15e-01 -1.32e-01 -1.35e-01 -1.31e-01  0.147268 1.126
4.36e-03 0.0909   *
36   6.64e-02 -5.17e-02 -5.96e-02 -6.08e-02 -5.91e-02  0.066386 1.132
8.86e-04 0.0909   *
37  -3.15e-01  2.46e-01  2.83e-01  2.89e-01  2.81e-01 -0.315448 1.100
1.99e-02 0.0909   *
38   1.47e-01 -1.15e-01 -1.32e-01 -1.35e-01 -1.31e-01  0.147268 1.126
4.36e-03 0.0909   *
39  -9.26e-01  7.22e-01  8.32e-01  8.48e-01  8.24e-01 -0.926059 0.882
1.64e-01 0.0909   *


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