Firm-product data provide information for various research questions in international trade or innovation economics. However, working with this data requires harmonizing product classifications consistently over time to avoid internal validity issues. The researcher must consider product code...

Accurately classifying products is essential in international trade. Virtually all countries categorize products into tariff lines using the Harmonized System (HS) nomenclature for both statistical and duty collection purposes. In this paper, we apply and assess several different algorithms to...