anchor.diff:     utf8_1.1.4.tar.gz \
      fansi_0.4.0.tar.gz \
      pillar_1.3.1.tar.gz \
  +   pkgconfig_2.0.2.tar.gz
      tibble_2.1.1.tar.gz \
      ggplot2_3.1.0.tar.gz \
      stargazer_5.2.2.tar.gz \
  
positive.code:    https://archive.linux.duke.edu/cran/src/contrib/openintro_1.7.1.tar.gz \
     https://archive.linux.duke.edu/cran/src/contrib/bindr_0.1.1.tar.gz \
     https://archive.linux.duke.edu/cran/src/contrib/bindrcpp_0.2.2.tar.gz \
     https://archive.linux.duke.edu/cran/src/contrib/pkgconfig_2.0.2.tar.gz \
     https://archive.linux.duke.edu/cran/src/contrib/plogr_0.2.0.tar.gz \
     https://archive.linux.duke.edu/cran/src/contrib/purrr_0.2.5.tar.gz \
     https://archive.linux.duke.edu/cran/src/contrib/tidyselect_0.2.4.tar.gz \
  
negative.code:    utf8_1.1.4.tar.gz \
     fansi_0.4.0.tar.gz \
     pillar_1.3.1.tar.gz \
     pkgconfig_2.0.2.tar.gz
     tibble_2.1.1.tar.gz \
     ggplot2_3.1.0.tar.gz \
     stargazer_5.2.2.tar.gz \
  