Search results for "management economics"
showing 10 items of 23 documents
Analyzing structural change : the biproportional mean filter and the biproportional bimarkovian filter
1998
The biproportional filter was created to analyze structural change between two input-output matrices by removing the effect of differential growth of sectors without predetermining if the model is demand or supply-driven, but with the disadvantage that projecting a first matrix on a second is not the same thing than projecting the second matrix on the first. Here two alternative methods are proposed which has not this last drawback, with the additional advantage for the biproportional bimarkovian filter that effects of sector size are also removed. Methods are compared with an application for France for 1980 and 1996.
On Boolean topological methods of structural analysis
2001
The properties of Boolean methods of structural analysis are used to analyze the intern structure of linear or non linear models. Here they are studied on the particular example of qualitative methods of input-output analysis. First, it is shown that these methods generate informational problems like biases when working in money terms instead of percentages, losses of information, increasing of computation time, and so on. Second, considering three ways to do structural analysis, analysis from the inverse matrix, from the direct matrix and from layers (intermediate flow matrices), these methods induce topological problems; the adjacency of the adjacency cannot be defined from the inverse ma…
On the consistency of the commodity-based technology in make-use model of production
2001
In the Stone make-use model, the industry-based technology is consistent because his solution can be explained in variational terms inside a circuit. However, the alternative model, the commodity-based technology, is not economically realistic: it never corresponds to a circuit, even if an exact solution can be found when the number of commodities is equal to the number of industries. This model hesitates between a supply-driven and a demand-driven model but when it is converted into a true supply-driven one, it retrieves a consistency.
Qualitative methods of structural analysis : layer-based methods are informationally trivial
2000
Some methods of qualitative structural analysis, as MFA, are based on the analysis of layers (flow matrices generated at each iteration when the equilibrium of an input-output model is computed). MFA mixes the analysis of the pure structure of production (the technical coefficients) and of the final demand. I have demonstrated that all column-coefficient matrices (or row-coefficient matrices) computed from each layer are the same in MFA: the information brought by one layer is identical to those of another layer. For a given structure of production, the only element of variability over layers is caused by the flows that final demand generates.If the new definition of layers proposed by the …
The Thunen's rent rediscovered (some reflections on the history of spatial thought)
1989
Von Thünen’s thought about land rent has often been oversimplified by modern economists: the aim of this paper is to analyse the properties of the original rent function of The Isolated State. We give a mathematical reformulation of Thünen’s reasoning and we show its richness, its curiosities and olso its limits. None of the Thünen’s rent functions is linear, and the original model is anable to assure that they are decreasing with distance to the center.
True prices, latent prices and the Ghosh model : some inconsistencies
2001
Beside the traditional Leontief demand-driven model, there is the Ghosh supply-driven model. This paper explores the typology of the possible models: demand driven models versus supply driven models, true prices versus latent (or index) prices, coefficients in physical terms versus coefficients in value. This demonstrates that the supply-driven model offers results of limited interest, being incapable to separate quantities and prices; and it is only when a very strange hypothesis is chosen -- demand prices, controlled by the buyer -- that the supply-driven model gives an interesting result with a separation between quantities and prices in the solution, becoming the dual of the Leontief mo…
Modelling suburbanization (success and limits of microeconomics of cities)
2001
History of population and employment suburbanization, mainly in the United States, suggests three characteristics of the phenomenon. 1/ Suburbanization results in urban sprawl in such a way that population and employment increase more rapidly in the periphery than in thecenter. 2/ Suburbanization leads to the emergence of new activity centers in the periphery and gives rise to multicentric urban structures. 3/ Suburbanization différenciâtes the economic contents and functions of these activity centers and brings a new organization of urban centres.In this framework, suburbanization takes different forms depending of periods and regions. The emergence of centers and the transformation from m…
Failure of the normalization of the RAS method : absorption and fabrication effects are still incorrect
2000
The r and s vectors of the RAS method of updating matrices are presented often as corresponding to an absorption effect and a fabrication effect. Here, it is proved that these vectors are not identified, so their interpretation in terms of fabrication and absorption effect is incorrect and even if a normalization was proposed to remove underidentification, this normalization fails and poses many difficulties.. Keywords : Input-Output ; RAS ; Biproportion
About the reinterpretation of the Ghosh model as a price model
2001
The Ghosh model assumes that, in an input-output framework, each commodity is sold to each sector in fixed proportions. This model is strongly criticized because it seems implausible in the traditional input-output field. To answer to these critics, Dietzenbacher stresses that it can be reinterpreted as a price model: the Leontief price model is equivalent to the Ghosh model when this one is interpreted as a price model. This paper shows that the interpretation of the Ghosh model as a price model cannot be accepted because Dietzenbacher makes a strong assumption, dichotomy, while the Ghosh model does not determine prices...
Financement des investissements et calculs de rentabilité
1988
L'objet de cet exposé est de fournir quelques éléments sur la prise en compte du financement des investissements lors des calculs de rentabilité. La première partie (section 1) sera consacrée à la comparaison des calculs de rentabilité globale et des calculs de rentabilité des capitaux propres dansle cas où l'on suppose qu'il n'y a pas de rationnement du capital