## COMMON AND SPECIFIC ATTRIBUTION OF YIELDS

Let us assume that a table is a marginal product of the two productive means, wood and labor. The marginal utility of the table is n; 20 l hours of labor and 10 w of wood are required. So long as these are our only data, the attribution of yields cannot be carried out. There are two unknown quantities I and w and only one equation. Let us assume that a chest is another marginal product of the same two goods. If it happens that the expenditure is the same in this case, i. e., I and 10 w are required, then the marginal utility n is probably correct. We would be no nearer the solution of our problem, for there would be no new equation, but only a repetition of the first one. However, if marginal products of these goods are found in which the ratio of the two quantities varies, or for which new equations may be formed by combining the two productive means with other cost-means, the case will be different. There is no doubt that such equations may be found. There are many more variations of the cost-elements, labor, wood, coal, iron and others, than there are types of cost element. The problem of attribution is solved if this is so. A definite magnitude may be computed for I and w. Thus we shall be able to ascertain the amount to which 20 I and 10 w participate in the yield. Just as we are able to make these theoretical calculations, the producer has a basis on which he may find the solution of his particular problem through trial and error.