Dear Professor King, I was doing some literature reading and I came across your software. I try the package with my own data but I got some error. I modified my data and make it look like the example data in the file path of the package. yourprep runs smoothly with some data like below: dta$data$`204500` rspi2 popu2 time 2004 NA 4858042 1994 2005 NA 4785805 1995 2006 NA 4704201 1996 2007 0.006431800 4592693 1997 2008 0.005454000 4522168 1998 2009 0.005908178 4432729 1999 2010 0.005238223 4317368 2000 2011 0.005180368 4237330 2001 2012 0.004544100 4176305 2002 2013 0.004363600 4098927 2003 2014 0.003821751 4056178 2004 2015 0.003390900 3958900 2005 2016 NA NA 2006 2017 NA NA 2007 2018 NA NA 2008 2019 NA NA 2009 2020 NA NA 2010 2021 NA NA 2011 2022 NA NA 2012 2023 NA NA 2013 2024 NA NA 2014 2025 NA NA 2015 But then I got error with yourcast() command. The scripts run below: + year.var=TRUE, sample.frame=c(2004,2015,2016,2025), + G.names="cntry.codes.txt", adjacency="adjacency.txt", + verbose=TRUE,summary=FALSE) Loading cross section files and checking for errors... csid204500.txt csid204501.txt csid204505.txt csid204510.txt csid204515.txt csid204520.txt csid204525.txt csid204530.txt csid204535.txt csid204540.txt csid204545.txt csid204550.txt csid204555.txt csid204560.txt csid204565.txt csid204570.txt csid204575.txt csid204580.txt csid204585.txt Loading auxiliary files... cntry.codes.txt adjacency.txt ...Finished Total number of cross sections: 19 ylc <- yourcast(formula=log(rspi2/popu2) ~ time, dataobj=dta, model="LC",debug =TRUE) Error in seq.default(smpvec[ind], smpvec[ln], by = 1) : wrong sign in 'by' argument Thank you for your help! Antonio Lam