AMONG the most elusive magnitudes to ,[_1quantify is the influence of technological change on employment, the reason being that technological change in any context has been difficult to isolate. Clearly, the traditional productivity ratios, such as output per unit of labor input, cannot be used to measure technological employment, since a productivity index embodies, in a seemingly indecomposable manner, the effects of in capital utilized, returns to scale, neutral and non-neutral technological change, and relative factor prices. Thus, in order to construct a measure of technological employment, we need to be able to quantify, at the minimum, the effects of in technology separately from the other forces. Yet, these other forces have meaning in themselves. Therefore, we should like to isolate the effect on the change in employment of in the following: (a) the scale of output, (b) the relative prices of capital and labor (assuming, for simplicity, only two factors), (c) returns to scale, and (d) neutral and non-neutral technology.' The present paper presents a method of measuring the forces (a)-(d) on employment and tests it on data for the private domestic non-farm sector of the United States for the period 1890-1958.2 It does this in such a way as to avoid the problem of the interaction among the forces (a)-(d) -at least to a first-order approximation. Stated differently, our objective is to frame a general method of measurement which permits a quantitative distinction to be drawn between structural changes and demand in terms of their effect on employment.8 Since the method is general, the forces (a)-(d) can be quantified for any subset in the total employed; for example, skilled or unskilled labor, regional unemployment, etc. The only requirement is that we be able to estimate a demand relation for the subset in question. We should like to emphasize the methodological rather than the substantive aspects of this paper for several reasons. The principal reason, though, is that the data, by virtue of their aggregative nature (inter alia), are not suitable to the method we will apply. Also, since the method derives from the micro theory of the firm, it should be applied, at most, to industry data. In what follows, the method is first presented verbally as far as possible. This is followed by a more precise statement of the method which permits a confrontation with data. The empirical measures of the private domestic non-farm sector are then set out and discussed. An appendix embodies a discussion of the data used in the paper.

[In this paper, we focus on capital aggregation in a general equilibrium model of production. Various potential aggregates involving intrasectoral and intersectoral, as well as full aggregation are discussed in connection with the various aggregation procedures. It will be shown that the satisfaction of the Gorman conditions allows for full aggregation within a general equilibrium model of production. We shall derive new conditions for aggregation using a composite commodity approach that appears to be somewhat weaker than the conditions associated with restrictions-on-functional-form theorems. Our main conditions relate to the equality of sectoral labor shares. The data for testing those conditions appear to be readily available. It is shown that the equal labor share condition can be applied to models with joint and nonjoint products. In addition, the conditions for aggregation are derived for a model with many primary inputs and also for a model with unequal rates of depreciation. Two sections are devoted to the main correspondences between certain aggregation procedures in the literature from the point of view of a general equilibrium model. The implications of our analysis for the form of the unit cost function and of the aggregate production function are discussed. In particular, if our aggregation condition holds, then the aggregate production function can be Cobb-Douglas, if one of the sectoral forms is also Cobb-Douglas, irrespective of the forms of the other sectoral production functions.]