bal.cs.psa: no visible global function definition for 'hist'
bal.cs.psa: no visible global function definition for 'points'
bal.cs.psa: no visible global function definition for 'legend'
bal.fe.psa: no visible global function definition for 'fisher.test'
bal.ks.psa: no visible global function definition for 'ks.test'
bal.ms.psa: no visible global function definition for 'hist'
bal.ms.psa: no visible global function definition for 'points'
bal.ms.psa: no visible global function definition for 'legend'
box.psa: no visible global function definition for 'boxplot'
box.psa: no visible global function definition for 'points'
box.psa: no visible global function definition for 'text'
box.psa: no visible global function definition for 'axis'
box.psa: no visible global function definition for 'aggregate'
box.psa: no visible global function definition for 'lines'
box.psa: no visible global function definition for 'legend'
cat.psa: no visible global function definition for 'terrain.colors'
cat.psa: no visible global function definition for 'rect'
cat.psa: no visible global function definition for 'axis'
cat.psa: no visible global function definition for 'text'
cat.psa: no visible global function definition for 'legend'
circ.psa: no visible global function definition for 'par'
circ.psa: no visible binding for global variable 'var'
circ.psa: no visible global function definition for 'symbols'
circ.psa: no visible global function definition for 'legend'
circ.psa: no visible global function definition for 'abline'
circ.psa: no visible global function definition for 'segments'
circ.psa: no visible global function definition for 'points'
circ.psa: no visible global function definition for 'rug'
circ.psa: no visible global function definition for 'title'
circ.psa: no visible global function definition for 'qt'
cstrata.psa: no visible global function definition for 'quantile'
cstrata.psa: no visible global function definition for 'runif'
cstrata.psa: no visible global function definition for 'par'
cstrata.psa: no visible global function definition for 'points'
cstrata.psa: no visible global function definition for 'abline'
cv.bal.psa: no visible global function definition for 'var'
cv.bal.psa: no visible global function definition for 'sd'
cv.bal.psa: no visible global function definition for 'axis'
cv.bal.psa: no visible global function definition for 'points'
cv.bal.psa: no visible global function definition for 'lines'
cv.bal.psa: no visible global function definition for 'abline'
cv.bal.psa: no visible global function definition for 'box'
cv.bal.psa: no visible binding for global variable 'sd'
loess.psa: no visible global function definition for 'loess'
loess.psa: no visible global function definition for 'points'
loess.psa: no visible global function definition for 'quantile'
loess.psa: no visible global function definition for 'abline'
loess.psa: no visible global function definition for 'rug'
loess.psa: no visible global function definition for 'box'
loess.psa: no visible binding for global variable 'var'
loess.psa: no visible global function definition for 'na.omit'
loess.psa: no visible global function definition for 'sd'
Undefined global functions or variables:
  abline aggregate axis box boxplot fisher.test hist ks.test legend
  lines loess na.omit par points qt quantile rect rug runif sd segments
  symbols terrain.colors text title var
Consider adding
  importFrom("grDevices", "terrain.colors")
  importFrom("graphics", "abline", "axis", "box", "boxplot", "hist",
             "legend", "lines", "par", "points", "rect", "rug",
             "segments", "symbols", "text", "title")
  importFrom("stats", "aggregate", "fisher.test", "ks.test", "loess",
             "na.omit", "qt", "quantile", "runif", "sd", "var")
to your NAMESPACE file.