Using the content of a string into a regression loop

[Federico Antonioli]

Dears,

I have a string variable 'selected' in which a bunch of real variables' name actually existing in my dataset are enlisted.

* Example generated by -dataex-. For more info, type help dataex
clear
input long id int year str170 selected
411 2014 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
411 2016 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
411 2017 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
411 2018 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
411 2019 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
411 2020 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
591 2004 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
591 2005 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
591 2006 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
591 2007 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
591 2008 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
591 2010 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
591 2012 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
591 2013 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
591 2014 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
591 2015 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
591 2016 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
591 2017 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
591 2018 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
591 2019 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
591 2020 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
600 2004 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
600 2005 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
626 2016 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
626 2017 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
626 2018 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
626 2019 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
627 2014 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
627 2015 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
627 2016 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
627 2017 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
628 2015 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
628 2016 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
628 2017 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
628 2018 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
628 2019 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
638 2007 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
638 2008 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
638 2009 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
639 2010 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
639 2011 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
639 2012 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
639 2014 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
639 2015 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
639 2016 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
639 2017 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
639 2019 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
639 2020 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
641 2010 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
641 2011 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
641 2012 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
641 2013 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
641 2014 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
641 2015 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
641 2016 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
641 2017 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
641 2018 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
641 2019 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
641 2020 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
642 2005 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
642 2006 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
642 2007 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
642 2008 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
642 2009 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
642 2010 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
642 2011 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
642 2012 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
642 2013 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
642 2014 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
642 2015 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
642 2016 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
642 2017 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
642 2018 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
642 2019 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
642 2020 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
643 2004 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
644 2004 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
644 2005 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
644 2006 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
644 2007 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
644 2008 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
644 2009 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
644 2010 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
644 2011 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
644 2012 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
644 2013 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
644 2014 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
644 2015 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
644 2016 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
644 2017 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
644 2018 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
646 2004 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
646 2005 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
646 2006 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
646 2007 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
646 2008 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
646 2009 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
646 2010 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
646 2011 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
646 2012 "share_paid_hrs uaacov_se450 uaacov_se465 uaacov_se410 uaacov_se275 uaacov_se281 uaacov_se284 uaacov_se360 uaacov_se381 uaacov_se390 uaacov_se135 uaacov_se136 uaacov_se606"
end
format %ty year

What I would do is to tell Stata to actually use these variables within a regression, something like

forvalues i=2004(1)2020 {
xtreg var1 'varlist in `selected' if year==`i'
}

I have no idea how to tell Stata to pick the variables enlisted in 'selected' though.

Any help would be very appreciated,

Many thanks!

federico

[Andrew Musau]

help levelsof

In a panel dataset, an observation is a firm-year combination. Therefore, you cannot estimate a panel model restricting the sample to a single year. Perhaps you want regress instead of xtreg.

levelsof selected, local(selections)
forvalues i=2004/2020{
    foreach s of local selections{
        regress var1 `varlist' if  selected=="`s'" & year==`i'
    }
}

[Federico Antonioli]

Many thanks Andrew,

indeed, sorry for the typo.

Thank you also for the piece of code, the only thing is that it does not perform a regression accounting for the variables enlisted in the string selected.

Is there a way to tell Stata that the `varlist' to be used is the content of selected?

Thanks again

regards

F

[Federico Antonioli]

Many thanks Andrew,

indeed, sorry for the typo.

Thank you also for the piece of code, the only thing is that it does not perform a regression accounting for the variables enlisted in the string selected.

Is there a way to tell Stata that the `varlist' to be used is the content of selected?

Thanks again

regards

F

Perhaps solved using levelsof and generating a macro :

levelsof selected, local(variables)
macro selected `variables'
reg var1 $selected

[Nick Cox]

In what you've shown us the variable selected looks to be a constant. So if i understand this correctly, you can just choose one of its values.

local selected = selected[1] 

xtreg var1 `selected'

or even

xtreg var1 `=selected[1]'

Wanting to run this in particular years would mean extra syntax. if it makes sense at all.

[Federico Antonioli]

In what you've shown us the variable selected looks to be a constant. So if i understand this correctly, you can just choose one of its values.

local selected = selected[1]

xtreg var1 `selected'

or even

xtreg var1 `=selected[1]'

Wanting to run this in particular years would mean extra syntax. if it makes sense at all.

Thanks Nick,

indeed, it was constant (I had one selected for each year), while now it is year-specific.

What I am trying to do is to generate a new variable containing the elements that are in selected1 but not in selected2, and then use the elements enlisted there for regressions.

Now that is not constant anymore, I am struggling to understand how to generate such variable:

* Example generated by -dataex-. For more info, type help dataex
clear
input long id int year str125 selected1 str83 selected2
411 2014 "se475 se490 se495 se425 se430 se295 se296 se298 se345 se350 se356 se370 se135 se030 se050 se054 se021 se610 se621 se622 se631" "se441 se450 se465 se490 se495 se420 se425 se005 se260"                              
591 2014 "se475 se490 se495 se425 se430 se295 se296 se298 se345 se350 se356 se370 se135 se030 se050 se054 se021 se610 se621 se622 se631" "se441 se450 se465 se490 se495 se420 se425 se005 se260"                              
411 2016 "se446 se455 se465 se475 se490 se495 se420 se425 se430 se005 se260 se275 se281 se295 se296 se297 se298 se300 se331"             "se005 se260 se284 se295 se296 se331 se340 se345 se350 se360 se370 se375 se380 se135"
591 2016 "se446 se455 se465 se475 se490 se495 se420 se425 se430 se005 se260 se275 se281 se295 se296 se297 se298 se300 se331"             "se005 se260 se284 se295 se296 se331 se340 se345 se350 se360 se370 se375 se380 se135"
end
format %ty year

I tried with the following, but the difference is constant between years (I guess I am not telling Stata that each year should be a different 'list'?):

gen difference = ""
forvalues i=2004(1)2020 {
local list1_`i' = select_abs_logit 
local list2_`i' = select_abs_eco1
bys year : replace iv_abs_soc = "`: list list1_`i' - list2_`i''"
}

and

gen difference = ""
levelsof year, local(year) 
foreach s of local year {
local list1_`s' = select_abs_logit 
local list2_`s' = select_abs_eco1
bys year : replace iv_abs_soc = "`: list list1_`s' - list2_`s''"
}

The following would then be the regression using the year-specific content of difference.

Thanks again,

regards

F

[Nick Cox]

What you're talking about in #6 is much more complicated than you asked in #1 or #3 so even knowing what you want to do is getting harder, let alone advising you how to do it.

Among other details, I have no idea what you intend to do with a variable difference which you create as empty but then never change or use.

First, the effect of

local foo = bar

when bar is a variable is always

local foo = bar[1]

i.e. to use the value for the first observation in the dataset.

This behaviour is often a surprise but is documented e.g. at https://journals.sagepub.com/doi/pdf...6867X231175349 (which may be behind a paywall for you) or
Wernow, J. 2005. FAQ: I have an if or while command in my program that only seems to evaluate the first observation. What’s going on? http://www.stata.com/support/faqs/programming/if-command-versus-if-qualifier (which isn't).

That is, being inside a loop does not by itself mean that Stata will use a value of that variable that is different each time around the loop.

Second, you're conflating an attempt to loop over years with an attempt to run something by: years, which rarely makes sense.

This is only one step but it may help in indicating a first step to be followed by others.

gen long obs = _n

forval y = 2004/2020 {
    su obs if year == `y'
    local list1 = select_abs_logit[r(min)]
    local list2 = select_abs_ecol[r(min)]
    * do something using those lists for data for this year
}

See also

(I suspect part of what is going on here is that you have some experience in programming in quite different languages, and are struggling with what a local macro is and can do.)

[Federico Antonioli]

What you're talking about in #6 is much more complicated than you asked in #1 or #3 so even knowing what you want to do is getting harder, let alone advising you how to do it.

Among other details, I have no idea what you intend to do with a variable difference which you create as empty but then never change or use.

Thanks Nick, apologies for that, the code I posted should has been as (changes in red text)

gen difference = ""
forvalues i=2004(1)2020 {
local list1_`i' = select_abs_logit
local list2_`i' = select_abs_eco1
bys year : replace difference= "`: list list1_`i' - list2_`i''"
*this is what I intended to do with those lists, i.e. having enlisted those variables that are in list1 but not in list2*}

Inspired by your suggested code, I may have found a suitable solution (if you do not advise otherwise) :

forval i = 1/`=_N' {
    local list1 = select_abs_logit[`i']
    local list2 = select_abs_eco1[`i']
    replace difference= "`: list list1 - list2'" in `i'
}

The next step would be to estimate a logit model for each year, hence telling Stata to use the variables enlisted in difference (which is year-specific).

Perhaps a way could be :

local difference2014= difference[1]
*where [1] corresponds to 2014 and so on*
logit var1 `difference2014'

but if there is a way to wrap this up in a more compact code I would happy to learn it.

Thanks anyway,

regards

F

[Nick Cox]

Good that you found #7 helpful but I think I've already addressed your query by suggesting an overall strategy.

Now the problem is repeating a logit regression: different again from any previous post in the thread! However, that appears to be secondary detail.

What you have in #8 makes your problem much more complicated than I think it needs to be. If that's a misreading then I really don't understand what you want to do.

There is no need for, and no advantage in, compiling a variable -- here called difference -- observation by observation if its value is constant for each year. Also, putting lists of variable names into other variables is counter-productive as, at a minimum, you then need to take them out again. We've already seen that point.

[Hemanshu Kumar]

Just adding my voice here because like Nick, I too am rather mystified by your approach. Why are you using a string variable at all? A variable is a vector, and at least from your data example, it seems all you need is a scalar (here, perhaps a single macro), since all the elements of the vector are the same. That would make for far simpler code which would also be computationally more efficient. Or is the data example not representative of the overall dataset, where the string changes in some observations? Even if so, there seems to be sufficient redundancy here that one might think of simpler alternatives (perhaps a small collection of macros?)

[Federico Antonioli]

Just adding my voice here because like Nick, I too am rather mystified by your approach. Why are you using a string variable at all? A variable is a vector, and at least from your data example, it seems all you need is a scalar (here, perhaps a single macro), since all the elements of the vector are the same. That would make for far simpler code which would also be computationally more efficient. Or is the data example not representative of the overall dataset, where the string changes in some observations? Even if so, there seems to be sufficient redundancy here that one might think of simpler alternatives (perhaps a small collection of macros?)

Indeed, as shown later in #6 the elements are year-specific, hence changing between observations. I estimated many lasso through a panel to select significant variables and the only way I found to keep them was to enlist them into a string variable.

Anyway, I think I overcomplicated things, and a small collection of macros should work.

Thanks

F