Applies shrinkage to the regression coefficients in the discrete (logistic) part of the hurdle model. Default is Enabled. The initial versions of MAST contained a bug that was fixed in its R source in March 2020. However, for the sake of reproducibility the fix was released only on a topic branch in MAST Github  and the default version of MAST remained as is. To install the fixed version of MAST in R, run the following R script.
# Uninstall the default version of MAST, if it's installed.
# Install devtools, if it's not installed yet.
In Flow, the user can switch between the fixed and default version by selecting Fixed version or Default version, respectively. To disable the shrinkage altogether, choose Disabled.
 Finak, G., McDavid, A., Yajima, M., Deng, J., Gersuk, V., Shalek, A. K., ... & Linsley, P. S. (2015). MAST: a flexible statistical framework for assessing transcriptional changes and characterizing heterogeneity in single-cell RNA sequencing data. Genome biology, 16(1), 278.
 MAST topic branch that contains the regression coefficient shrinkage fix: