IS THE GHOSH MODEL INTERESTING?*

ABSTRACT The overall value of the Ghosh model is appraised. Its treatment of quantities and prices is scrutinized by examining the variant with data in quantities and prices, and the variant with data in value and price indexes. The methodology involves returning to the accounting equations and shows that: (i) the Ghosh model offers solutions of limited interest, being incapable of providing prices or price indexes separately from quantities; (ii) what is taken to be the equation of Ghosh's value model is actually that of Ghosh's physical model; (iii) the Ghosh model may serve for cost‐push exercises, but the dual of the Leontief model performs the same task in a much simpler and more natural way; and (iv) Cronin's mixed models do not actually mix Leontief and Ghosh hypotheses.     

À propos du colloque « The Machine as Model and Metaphor » Max-Planck-Institut für Wissenschaftsgeschichte Berlin,novembre 2006

Sans résumé ? Lève la peau, dissèque: ici commencent les machines. Puis, tu te perds dans une substance inexplicable, étrangère à tout ce que tu sais et qui est pourtant l’essentielle. ? Paul Valéry, Tel quel, Cahier B 1910 Ses recherches portent sur l’épistémologie, l’histoire des sciences et l’histoire de la philosophie à l’age classique (xvi ^e-xvii ^e siècles). Elle a notamment dirigé avec Walter Roy Laird, Mechanics and Natural Philosophy before the Scientific Revolution (Dortrecht/Boston/Londres, Kluwer Academic Publishers, 2007), puis, en collaboration avec Massimo Bucciantini et Michele Camerota, Mechanics and Cosmology in the Medieval and Early Modern Period (Florence, Olschki, 2007).     

Understanding the Shortcomings of Commodity‐based Technology in Input–Output Models: an Economic‐Circuit Approach

Abstract.  The Make‐Use Model serves as a basis for most national accounting systems as the System of National Accounts (SNA) and is acknowledged as the most suitable model for interregional analysis. Two hypotheses are traditionally made featuring either industry‐based technologies (IBT) or commodity‐based technologies (CBT). While industry‐based technologies can be easily interpreted in terms of a demand‐driven economic circuit, it will be shown that: (1) commodity‐based technologies cannot be interpreted as a demand‐driven economic circuit because this involves computing the inverse of a matrix (the matrix of industry output proportions), which is either impossible or generates negative terms; (2) the only way to obtain a plausible explanation of CBT is to convert it into a supply‐driven model. This provides a new reason for rejecting CBT: either IBT is adopted but violates Kop Jansen and ten Raa's axioms, or CBT is chosen but must be converted into a poor or unrealistic supply‐driven model.