----------------- HES POSTING ----------------- [This message appeared first on the Eh.Res list, but I thought members here would be interested in replying as well. -- RBE] In many textbooks - like P. Krugmann, International Economics (2000), page 163 - a simple diagram is used to illustrate the effects of international factor mobility between country A and country B. The horizontal axis represents the total stock of the factor in question. A schedule representing the decreasing marginal product of the factor for country A is drawn from the right axis, and a marginal product schedule for country B is drawn from the left axis. The diagram can also be found in the 1930's as an illustration of the marginal principle of dividing a given amount of a factor of production between to types of production. From where does this diagram originate? Who was the first to introduce it in the marginal productivity theory and in the theory of nternational economics? Niels-Henrik Topp Department of Political Science University of Copenhagen [log in to unmask] ------------ FOOTER TO HES POSTING ------------ For information, send the message "info HES" to [log in to unmask]