481 you will be required to complete a replication of John McCallum’s border puzzle in a gravity trade model. McCallum, J. œNational Borders Matter: Canada-U.S. Regional Trade Patterns, American Economic Review, 85(3), 1995 Your goal is to estimate the gravity model specification in Table 1, Columns (1)-(4) in the McCallum paper, and provide a write up of the analysis Your write up of the replication should include (i) A short introduction that motivates the estimation of a gravity model and the impact of national borders on trade. Be clear to explain why the US-Canada border is of particular interest in this context. (ii) A section that clearly details your empirical strategy. That is, you need to write out what the exact specification that your are running and define all variables. Also make predictions about what coefficients you expect to find, if any. (iii) A short section that interprets the border dummy, and a discussion of why you think the border effect is estimated to be so large. Finally, you will need to turn in a .do file from STATA that describes exactly how you took the raw data from excel to a STATA data file format, and shows exactly the commands you used to replicate McCallum’s table 1