DMR: no visible global function definition for 'lm'
DMR : <anonymous>: no visible global function definition for 'hclust'
DMR : <anonymous>: no visible global function definition for 'as.dist'
DMR: no visible global function definition for 'sd'
DMR: no visible binding for global variable 'sd'
DMR4glm: no visible global function definition for 'as.formula'
DMR4glm: no visible global function definition for 'glm'
DMR4glm : <anonymous>: no visible global function definition for
  'hclust'
DMR4glm : <anonymous>: no visible global function definition for
  'as.dist'
DMR4glm: no visible global function definition for 'sd'
DMR4glm: no visible binding for global variable 'sd'
cuth : <anonymous>: no visible global function definition for 'cutree'
cuth4glm: no visible global function definition for 'cutree'
cuth4glm: no visible global function definition for 'sd'
cuth4glm: no visible global function definition for 'glm'
cuth4glm: no visible global function definition for 'as.formula'
cuth4glm: no visible global function definition for 'logLik'
hip: no visible global function definition for 'adiag'
plot_bf: no visible global function definition for 'plot'
plot_bf: no visible global function definition for 'axis'
plot_bf: no visible global function definition for 'box'
plot_bf: no visible global function definition for 'lines'
plot_bf: no visible global function definition for 'abline'
plot_bf: no visible global function definition for 'grid'
stepDMR: no visible global function definition for 'lm'
stepDMR: no visible binding for global variable 'sd'
stepDMR: no visible global function definition for 'sd'
t_stats: no visible global function definition for 'combn'
Undefined global functions or variables:
  abline adiag as.dist as.formula axis box combn cutree glm grid hclust
  lines lm logLik plot sd
Consider adding
  importFrom("graphics", "abline", "axis", "box", "grid", "lines",
             "plot")
  importFrom("stats", "as.dist", "as.formula", "cutree", "glm", "hclust",
             "lm", "logLik", "sd")
  importFrom("utils", "combn")
to your NAMESPACE file.