diff --git a/Dockerfile b/Dockerfile
index 5daf4ed8f52054eda978ecd8aa2fe9fbc207c8ad..81308b71d5e9a26aafaf5df91c9fce45b4aebf04 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -181,6 +181,7 @@ RUN Rscript -e 'install.packages(c("iterators"))'
 RUN Rscript -e 'install.packages(c("rsample"))'
 RUN Rscript -e 'install.packages(c("Rcpp"))'
 RUN Rscript -e 'install.packages(c("rstan"))'
+RUN Rscript -e 'install.packages(c("gam"))'
 # install github packages
 RUN Rscript -e 'devtools::install_github(c("Vivianstats/scImpute", "theislab/kBET", "kieranrcampbell/ouija", "hemberg-lab/scfind"))'
 
diff --git a/course_files/figures/rotation2.png b/course_files/figures/rotation2.png
index 655a7b3b16da0649ea51250383e02d2216b1f8cf..df72366f4f91ddaa2ecedf2cee587391fe0a2f2d 100644
Binary files a/course_files/figures/rotation2.png and b/course_files/figures/rotation2.png differ