With whom does Canada compete in the US marketplace? : With whom does Canada compete in the United States marketplace?

We extend the existing literature by adopting a more structured analytic approach that examines all industry sectors for which the United States imports, and allows for the comparison of the interactions between any two nations (including the United States) that sell in US markets across all of the markets within which the nations sell in the United States. [...] The table lists the 10 US 4-digit NAIC sectors for which China had the largest gains in market share from 1998 to 2003, along with the significance of each of those sectors in Canadian exports to the United States. [...] China’s market share increased in six of the ten sectors having the largest decline in dollar value of Canadian exports to the United States from 1998 to 2003; remained at 0% in three of the sectors; and declined by just 0.1% in one sector. [...] Weaknesses of Focusing on Industry-By-Industry Comparisons An important limitation of the analysis so far (which is nevertheless actually quite representative of much of the current literature focusing on the competition for market share by countries in third markets) is that the pair-wise comparisons of detailed industries do not provide any quantifiable accounting of the impact of the breadth of [...] That is, MOMAB is a weighted average measure of nation B’s market share across all i industry sectors in which nation A sells to nation k. The weights reflect the importance of individual sectors of nation A’s exports to nation k, as measured by i's percentage share of nation A’s total sales to nation k. By summing the product of siA and msiB across all i sectors, the MOM captures both the breadth