CompLikelihood: no visible global function definition for 'optim'
Covariogram: no visible global function definition for 'uniroot'
Covariogram: no visible global function definition for 'pnorm'
Covariogram: no visible global function definition for 'par'
Covariogram: no visible global function definition for 'persp'
Covariogram: no visible global function definition for 'plot'
Covariogram: no visible global function definition for 'dev.cur'
Covariogram: no visible global function definition for 'lines'
Covariogram: no visible global function definition for 'abline'
Covariogram: no visible global function definition for 'points'
Covmatrix : Cmatrix: no visible global function definition for 'new'
FitGev: no visible global function definition for 'optim'
HypoTest: no visible global function definition for 'pchisq'
InitParam: no visible global function definition for 'var'
InitParam: no visible global function definition for 'qnorm'
Kri: no visible global function definition for 'window'
Likelihood : LogNormDenTap: no visible global function definition for
  'new'
Likelihood : LogNormDenTap: no visible global function definition for
  'slot<-'
Likelihood: no visible global function definition for 'optim'
Likelihood: no visible global function definition for 'new'
Likelihood: no visible global function definition for 'slot<-'
MomEst: no visible global function definition for 'var'
RFsim : CholRFsim: no visible global function definition for 'rnorm'
WLeastSquare: no visible global function definition for 'optim'
WlsInit: no visible global function definition for 'optim'
Undefined global functions or variables:
  abline dev.cur lines new optim par pchisq persp plot pnorm points
  qnorm rnorm slot<- uniroot var window
Consider adding
  importFrom("grDevices", "dev.cur")
  importFrom("graphics", "abline", "lines", "par", "persp", "plot",
             "points")
  importFrom("methods", "new", "slot<-")
  importFrom("stats", "optim", "pchisq", "pnorm", "qnorm", "rnorm",
             "uniroot", "var", "window")
to your NAMESPACE file (and ensure that your DESCRIPTION Imports field
contains 'methods').