Documentation for the package https://cran.r-project.org/web/packages/matchingMarkets/matchingMarkets.pdf
On page 32, how is c1:s1 computed in the data on running the following example code:
3. Correction for sorting bias when match valuations V are unobserved ## 3-a. Run Gibbs sampler (when SEL is given)
fit2 <- stabit2(OUT = xdata$OUT,
SEL = xdata$SEL,
outcome = y ~ c1:s1,
selection = ~-1 + c1:s1, niter=1000 )