Intensive and Extensive Margins (Hummels and Klenow, 2005)

I would like to discuss some questions about the commands of Intensive and Extensive Margin (Hummels and Klenow, 2005)in Stata.

In my database I have the value of exports (tradevalue) of 5000 varieties of products (commodities) for 15 years (year), the five BRICS countries (exporter) to 59 importing countries (importer). So I wonder if the correct way to calculate the extensive and intensive margins would be:

hummels tradevalue, j (exporter) m (importer) i (commodities)

or

hummels tradevalue, j (exporter) m (importer) i (commodities) by (year) outfile

The estimated values of the margins should be between 0 and 1?


Best regards,

Juliana de Sales Silva