Error(s) in re-building vignettes:
  ...
--- re-building 'automatic_groups_with_groupdata2.Rmd' using rmarkdown

Attaching package: 'dplyr'

The following objects are masked from 'package:stats':

    filter, lag

The following objects are masked from 'package:base':

    intersect, setdiff, setequal, union

--- finished re-building 'automatic_groups_with_groupdata2.Rmd'

--- re-building 'cross-validation_with_groupdata2.Rmd' using rmarkdown

Attaching package: 'dplyr'

The following objects are masked from 'package:stats':

    filter, lag

The following objects are masked from 'package:base':

    intersect, setdiff, setequal, union

Loading required package: lme4
Loading required package: Matrix

Attaching package: 'lmerTest'

The following object is masked from 'package:lme4':

    lmer

The following object is masked from 'package:stats':

    step

Loading required package: zoo

Attaching package: 'zoo'

The following objects are masked from 'package:base':

    as.Date, as.Date.numeric

Quitting from lines 139-147 (cross-validation_with_groupdata2.Rmd) 
Error: processing vignette 'cross-validation_with_groupdata2.Rmd' failed with diagnostics:
there is no package called 'xpectr'
--- failed re-building 'cross-validation_with_groupdata2.Rmd'

--- re-building 'description_of_groupdata2.Rmd' using rmarkdown

Attaching package: 'dplyr'

The following objects are masked from 'package:stats':

    filter, lag

The following objects are masked from 'package:base':

    intersect, setdiff, setequal, union

--- finished re-building 'description_of_groupdata2.Rmd'

--- re-building 'introduction_to_groupdata2.Rmd' using rmarkdown
--- finished re-building 'introduction_to_groupdata2.Rmd'

--- re-building 'time_series_with_groupdata2.Rmd' using rmarkdown

Attaching package: 'dplyr'

The following objects are masked from 'package:stats':

    filter, lag

The following objects are masked from 'package:base':

    intersect, setdiff, setequal, union

Don't know how to automatically pick scale for object of type <ts>. Defaulting
to continuous.
--- finished re-building 'time_series_with_groupdata2.Rmd'

SUMMARY: processing the following file failed:
  'cross-validation_with_groupdata2.Rmd'

Error: Vignette re-building failed.
Execution halted