[R] help with kolmogorov smirnov test

[Agnes Gault]

Hello!

I am an 'R beginner'. I am trying to check if my data follow a negative 
binomial function.
the command i've typed in is:

 >  nbdo=rnegbin(58,mu=27.82759,theta=0.7349851)
 > ks.test(do$DO,nbdo)
Each time i do that, p given is different and i get this warning message:

'Warning message:
cannot compute correct p-values with ties in: ks.test(do$DO, nbdo) '

Could someone tell me what's wrong? What does 'with ties in' mean?

Thank you!


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Agnès GAULT
graduate student
UMR 5173 MNHN-CNRS
case postale 50
Species Conservation, Restoration and Population Survey (CERSP)
61 rue Buffon, 1er étage
75005 PARIS
FRANCE
Tel: 33 (0)1 40 79 57 64
Fax: 33 (0)1 40 79 38 35
Email: gault at mnhn.fr