[R] Strange warning in summary.lm

[Uwe Ligges]

ONKELINX, Thierry wrote:
> Dear useRs,
> 
> Lately I noticed a strange warning in the summary of a lm-object. Any
> idea what this warning is about? I'm using R 2.5.1 on Win XP pro.
> 
>> x <- rnorm(100)
>> y <- rnorm(100)
>> summary(lm(y~x))
> 
> Call:
> lm(formula = y ~ x)
> 
> Residuals:
>      Min       1Q   Median       3Q      Max 
> -1,77809 -0,68438 -0,04409  0,63891  2,30863 
> 
> Coefficients:
>             Estimate Std. Error t value Pr(>|t|)
> (Intercept) -0,00217    0,09244  -0,023    0,981
> x            0,01315    0,09628   0,137    0,892
> 
> Residual standard error: 0,9236 on 98 degrees of freedom
> Multiple R-Squared: 0.0001903,  Adjusted R-squared: -0.01001 
> F-statistic: 0.01866 on 1 and 98 DF,  p-value: 0,8916 
> 
> Warning message:
> NAs introduced by coercion in: as.double.default(Cf[okP]) 

Probably you have an object in your workspace or another attached 
environment in the search path that conflicts with objects that are 
required to call summary(lm(...)). E.g. some lm... oder summary... function?

Best,
Uwe Ligges



> 	
> Thanks,
> 
> Thierry
> 
> ------------------------------------------------------------------------
> ----
> ir. Thierry Onkelinx
> Instituut voor natuur- en bosonderzoek / Research Institute for Nature
> and Forest
> Cel biometrie, methodologie en kwaliteitszorg / Section biometrics,
> methodology and quality assurance
> Gaverstraat 4
> 9500 Geraardsbergen
> Belgium
> tel. + 32 54/436 185
> Thierry.Onkelinx at inbo.be
> www.inbo.be 
> 
> Do not put your faith in what statistics say until you have carefully
> considered what they do not say.  ~William W. Watt
> A statistical analysis, properly conducted, is a delicate dissection of
> uncertainties, a surgery of suppositions. ~M.J.Moroney
> 
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