.ls.objects: no visible binding for global variable 'object.size'
.onAttach: no visible global function definition for
  'packageDescription'
print.summary.pwfe: no visible global function definition for
  'printCoefmat'
print.summary.wfe: no visible global function definition for
  'printCoefmat'
print.summary.wfedid: no visible global function definition for
  'printCoefmat'
pwfe: no visible global function definition for 'na.omit'
pwfe: no visible global function definition for 'as.formula'
pwfe: no visible global function definition for 'flush.console'
pwfe: no visible global function definition for 'binomial'
pwfe: no visible global function definition for 'fitted'
pwfe: no visible global function definition for 'lm'
pwfe: no visible global function definition for 'model.frame'
pwfe: no visible global function definition for 'model.matrix'
pwfe: no visible global function definition for 'model.response'
pwfe: no visible global function definition for 'resid'
pwfe: no visible global function definition for 'vcov'
pwfe: no visible global function definition for 'pchisq'
summary.pwfe: no visible global function definition for 'coef'
summary.pwfe: no visible global function definition for 'pt'
summary.wfe: no visible global function definition for 'coef'
summary.wfe: no visible global function definition for 'pt'
summary.wfedid: no visible global function definition for 'pt'
wfe: no visible global function definition for 'model.frame'
wfe: no visible global function definition for 'model.matrix'
wfe: no visible global function definition for 'model.response'
wfe: no visible global function definition for 'na.omit'
wfe: no visible global function definition for 'flush.console'
wfe: no visible global function definition for 'as.formula'
wfe: no visible global function definition for 'lm'
wfe: no visible global function definition for 'vcov'
wfe: no visible global function definition for 'pchisq'
wfe: no visible global function definition for 'as'
Undefined global functions or variables:
  as as.formula binomial coef fitted flush.console lm model.frame
  model.matrix model.response na.omit object.size packageDescription
  pchisq printCoefmat pt resid vcov
Consider adding
  importFrom("methods", "as")
  importFrom("stats", "as.formula", "binomial", "coef", "fitted", "lm",
             "model.frame", "model.matrix", "model.response", "na.omit",
             "pchisq", "printCoefmat", "pt", "resid", "vcov")
  importFrom("utils", "flush.console", "object.size",
             "packageDescription")
to your NAMESPACE file (and ensure that your DESCRIPTION Imports field
contains 'methods').