Error(s) in re-building vignettes:
  ...
--- re-building 'mlergm_tutorial.Rmd' using rmarkdown
Loading required package: ergm
Loading required package: network
network: Classes for Relational Data
Version 1.16.1 created on 2020-10-06.
copyright (c) 2005, Carter T. Butts, University of California-Irvine
                    Mark S. Handcock, University of California -- Los Angeles
                    David R. Hunter, Penn State University
                    Martina Morris, University of Washington
                    Skye Bender-deMoll, University of Washington
 For citation information, type citation("network").
 Type help("network-package") to get started.


ergm: version 3.11.0, created on 2020-10-14
Copyright (c) 2020, Mark S. Handcock, University of California -- Los Angeles
                    David R. Hunter, Penn State University
                    Carter T. Butts, University of California -- Irvine
                    Steven M. Goodreau, University of Washington
                    Pavel N. Krivitsky, UNSW Sydney
                    Martina Morris, University of Washington
                    with contributions from
                    Li Wang
                    Kirk Li, University of Washington
                    Skye Bender-deMoll, University of Washington
                    Chad Klumb
                    Michal Bojanowski, Kozminski University
                    Ben Bolker
Based on "statnet" project software (statnet.org).
For license and citation information see statnet.org/attribution
or type citation("ergm").

NOTE: Versions before 3.6.1 had a bug in the implementation of the bd()
constraint which distorted the sampled distribution somewhat. In
addition, Sampson's Monks datasets had mislabeled vertices. See the
NEWS and the documentation for more details.

NOTE: Some common term arguments pertaining to vertex attribute and
level selection have changed in 3.10.0. See terms help for more
details. Use 'options(ergm.term=list(version="3.9.4"))' to use old
behavior.

Quitting from lines 114-122 (mlergm_tutorial.Rmd) 
Error: processing vignette 'mlergm_tutorial.Rmd' failed with diagnostics:
attempt to set index 0/0 in SET_VECTOR_ELT
--- failed re-building 'mlergm_tutorial.Rmd'

SUMMARY: processing the following file failed:
  'mlergm_tutorial.Rmd'

Error: Vignette re-building failed.
Execution halted