Error(s) in re-building vignettes:
--- re-building ‘README.Rmd’ using rmarkdown
Warning: Use of `Interval.change.df$Interval` is discouraged. Use `Interval` instead.
Warning: Use of `gross.m$categories` is discouraged. Use `categories` instead.
Warning: Use of `gross.m$value` is discouraged. Use `value` instead.
Warning: Use of `gross.m$variable` is discouraged. Use `variable` instead.
Warning: Use of `gross.intensity.m$categories` is discouraged. Use `categories` instead.
Warning: Use of `gross.intensity.m$value` is discouraged. Use `value` instead.
Warning: Use of `gross.intensity.m$variable` is discouraged. Use `variable` instead.
Warning: Use of `gross.intensity.m$variable` is discouraged. Use `variable` instead.
Warning: Use of `gross.intensity.m$variable` is discouraged. Use `variable` instead.
Warning: Use of `gross.m$categories` is discouraged. Use `categories` instead.
Warning: Use of `gross.m$value` is discouraged. Use `value` instead.
Warning: Use of `gross.m$variable` is discouraged. Use `variable` instead.
Warning: Use of `gross.intensity.m$categories` is discouraged. Use `categories` instead.
Warning: Use of `gross.intensity.m$value` is discouraged. Use `value` instead.
Warning: Use of `gross.intensity.m$variable` is discouraged. Use `variable` instead.
Warning: Use of `gross.intensity.m$variable` is discouraged. Use `variable` instead.
Warning: Use of `gross.intensity.m$variable` is discouraged. Use `variable` instead.
dyld: lazy symbol binding failed: Symbol not found: ____chkstk_darwin
  Referenced from: /usr/local/bin/pandoc (which was built for Mac OS X 10.15)
  Expected in: /usr/lib/libSystem.B.dylib

dyld: Symbol not found: ____chkstk_darwin
  Referenced from: /usr/local/bin/pandoc (which was built for Mac OS X 10.15)
  Expected in: /usr/lib/libSystem.B.dylib

Error: processing vignette 'README.Rmd' failed with diagnostics:
pandoc document conversion failed with error 6
--- failed re-building ‘README.Rmd’

SUMMARY: processing the following file failed:
  ‘README.Rmd’

Error: Vignette re-building failed.
Execution halted