odc: no visible global function definition for ‘model.frame’
odc: no visible global function definition for ‘model.matrix’
odc: no visible global function definition for ‘model.response’
odc: no visible global function definition for ‘median’
odc: no visible global function definition for ‘qnorm’
plot,OutlierDC: no visible global function definition for ‘model.frame’
plot,OutlierDC: no visible global function definition for
  ‘model.response’
plot,OutlierDC: no visible global function definition for ‘grid’
plot,OutlierDC: no visible global function definition for ‘points’
plot,OutlierDC: no visible global function definition for ‘abline’
plot,OutlierDC: no visible global function definition for ‘legend’
plot,OutlierDC: no visible global function definition for ‘qqnorm’
plot,OutlierDC: no visible global function definition for ‘qqline’
plot,OutlierDC: no visible global function definition for
  ‘model.matrix’
plot,OutlierDC: no visible global function definition for ‘lines’
plot,OutlierDC: no visible global function definition for ‘axis’
plot,OutlierDC: no visible global function definition for ‘quantile’
plot,OutlierDC: no visible global function definition for ‘box’
plot,OutlierDC: no visible global function definition for ‘rug’
show,OutlierDC: no visible global function definition for ‘model.frame’
show,OutlierDC: no visible global function definition for
  ‘model.response’
show,OutlierDC: no visible global function definition for
  ‘model.matrix’
show,OutlierDC: no visible global function definition for ‘head’
show,OutlierDC: no visible global function definition for ‘tail’
update,OutlierDC: no visible global function definition for
  ‘model.frame’
update,OutlierDC: no visible global function definition for
  ‘model.response’
Undefined global functions or variables:
  abline axis box grid head legend lines median model.frame
  model.matrix model.response points qnorm qqline qqnorm quantile rug
  tail
Consider adding
  importFrom("graphics", "abline", "axis", "box", "grid", "legend",
             "lines", "points", "rug")
  importFrom("stats", "median", "model.frame", "model.matrix",
             "model.response", "qnorm", "qqline", "qqnorm", "quantile")
  importFrom("utils", "head", "tail")
to your NAMESPACE file.