{smcl} {* *! version 1.0 Aug2014}{...} {cmd:help nredound}{right: ({browse "http://www.stata-journal.com/article.html?article=st0409":SJ15-3: st0409})} {hline} {title:Title} {p2colset 5 17 19 2}{...} {p2col :{cmd:nredound} {hline 2}}Estimate the number of redundant parameters within the specified list of fixed effects{p_end} {p2colreset}{...} {marker syntax}{...} {title:Syntax} {p 8 17 2} {cmdab:nredound} {varlist} {ifin} {marker description}{...} {title:Description} {pstd} {cmd:nredound} uses an algorithm based on the one described in Abowd, Creecy, and Kramarz (2002) to calculate the number of redundant parameters within the specified list of categorical variables in {varlist}. {title:Remarks} {pstd} The program uses the commands {helpb a2group}, {helpb tuples}, and {helpb distinct}. {marker examples}{...} {title:Examples} {phang}{cmd:. webuse nlswork}{p_end} {phang}{cmd:. nredound ind_code occ_code idcode year}{p_end} {phang}{cmd:. nredound ind_code occ_code idcode year if age>15}{p_end} {title:Stored results} {pstd} {cmd:nredound} stores the following in {cmd:e()}: {synoptset 20 tabbed}{...} {p2col 5 20 24 2: Scalars}{p_end} {synopt:{cmd:e(M)}}the number of redundant parameters{p_end} {title:Reference} {phang} Abowd, J. M., R. H. Creecy, and F. Kramarz. 2002. Computing person and firm effects using linked longitudinal employer-employee data. Technical Paper No. TP-2002-06, Center for Economic Studies, U.S. Census Bureau. {browse "http://www2.census.gov/ces/tp/tp-2002-06.pdf"}. {marker Author}{...} {title:Author} {pstd}Fernando Rios-Avila{break} Levy Economics Institute of Bard College{break} Blithewood-Bard College{break} Annandale-on-Hudson, NY{break} friosavi@levy.org {marker also_see}{...} {title:Also see} {p 4 14 2}Article: {it:Stata Journal}, volume 15, number 3: {browse "http://www.stata-journal.com/article.html?article=st0409":st0409}{p_end}