journal of urban economics 50 191h5008229 2001 doi 10 1006pi114juec 2230 available online at http pi114pi114www idealibrary com on the determinants agglomeration 1 stuart s rosenthal department center for policy research syracuse university new york 13244 1020 e mail ssrosent maxwell syr edu and william c strange faculty commerce business administration british columbia vancouver v6t 1z2 canada ubc ca received may 23 2000 revised april published july 20 this paper examines microfoundations economies us manufacturing industries using as observations we regress ellisonh5008 glaeser g ellison 1997 j polit econ 105 889h5008927 measure spatial concentration industry characteristics that proxy presence knowl edge spillovers labor market pooling input sharing product shipping costs natural advantage analysis is conducted separately zipcode county state levels results indicate proxies have most robust effect positively influencing all geography knowledge in contrast affect only level reliance manufactured inputs or
