| 1. |
- Andersson, M., et al.
(författare)
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Dynamics of entry and exit of product varieties : What evolution dynamics can account for the empirical regularities?
- 2011
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Ingår i: Nonlinear Economic Dynamics. - : Nova Science Publishers, Inc.. - 9781616687885 ; , s. 155-174
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Bokkapitel (refereegranskat)abstract
- Firm-level heterogeneity is substantial even in narrowly defined industries. This chapter focuses on formulating evolution dynamics which can account for the observed heterogeneity and its maintenance. Based on examination of data on Swedish firms' supply pattern across different markets over time, we present a parsimonious model that has the ambition to capture the picture of heterogeneous firms, while accommodating the simultaneous exit and entry of destination varieties in firms' supply pattern. The model assumes both scale economies of firms and path-dependence, where the latter is manifested in such a way that the arrival rate of innovation ideas to an individual firm is a function of each firm's stock of varieties at every given point in time. The path-dependence phenomenon is an "explosive" non-linearity, whereas conservation mechanisms include development of demand and exit of established varieties. The described path dependence explains the skewed distribution of varieties across firms. Exit of obsolete varieties and growth of demand keep the "equilibrium" away from competitive exclusion where only few large firms remain. We make use of simulations to depict and assess the innovation dynamics of the proposed model.
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| 2. |
- Cánovas, J.S., et al.
(författare)
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On the dynamics of a piecewise linear oligopoly model with capacity limits and reinvestment periods
- 2011
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Ingår i: Nonlinear economic dynamics. - : Nova Science Publishers, Inc.. - 9781616687885 ; , s. 237-257
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Bokkapitel (refereegranskat)abstract
- In this chapter we study the stability problem for an oligopoly market when the number of competitors grows. It has been pointed out that Cournot oligopoly is destabilized when the number of competitors grows beyond a very small number. However, all such studies concerned models with firms facing constant marginal costs. If one is interested in the question whether a Cournot equilibrium smoothly transforms into a perfect competition equilibrium when the number of competitors grows, the instability pointed out is neither surprising nor very relevant. In the competitive market we assume many small firms, whereas in the oligopoly there are few big firms. A firm with constant marginal costs is potentially infinitely large. So, to take this in consideration, we introduce capacity limits due to fixed amounts of capital which only occasionally are changed due to replacements of worn out capital. We find that the Cournot equilibrium destabilizes depending on the number of firms, but also on the way they choose the investment periods. Anyway, the oligopoly market becomes more complex when the number of firms increases.
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| 3. |
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| 4. |
- Panchuk, Anastesiia, et al.
(författare)
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Industry dynamics, stability of cournot equilibrium, and renewal of capital
- 2011
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Ingår i: Nonlinear economic dynamics. - : Nova Science Publishers, Inc.. - 9781616687885 ; , s. 259-275
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Bokkapitel (refereegranskat)abstract
- This chapter focuses industrial dynamics of an oligopoly market with increasing competition where the firms enter one by one. At the moment of entry each firm chooses capital stock of a size corresponding to current market conditions. According to the assumed production technology (a CES function with constant returns and substitution elasticity equal to 0.5), at the moments of investment the firms access a constant returns technology, whereas in between they produce with decreasing returns - even with capacity bounds due to the fixed capital stock. Once capital has worn out, it is renewed, again under constant returns. This puts up a mixed dynamics of short and long run adjustment, with some firms constrained by fixed capital stocks, others entering or reinvesting. Two scenarios under these assumptions are focused; one where the durability of capital is very long compared to the ultimate number of competitors; another where capital just lasts two periods so that the firms fall in two categories which take turns in reinvesting.
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| 5. |
- Puu, Tönu, 1936-
(författare)
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Dynamics of stackelberg duopoly
- 2011
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Ingår i: Nonlinear economic dynamics. - : Nova Science Publishers, Inc.. - 9781616687885 ; , s. 287-303
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Bokkapitel (refereegranskat)abstract
- Stackelberg leadership is understood as a stationary supply taking account of the follower's Cournot reaction function. However, given the follower always adheres to the reaction function, the leader could also choose a dynamic, for instance, periodic sales policy over time. Using Stackelberg's exponential inverse demand function, it is shown that such periodic policies indeed are more advantageous than the stationary solution. Simple orbits can be learned by the follower, and adaptation then throws the system back to the stationary case. It is, however, shown how the leader can choose long-period orbits of sufficient irregularity (of even random or chaotic appearance) so as to prevent the follower from such learning.
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| 6. |
- Puu, Tönu, 1936-
(författare)
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Nonlinear economic dynamics and global analysis
- 2011
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Ingår i: Nonlinear economic dynamics. - : Nova Science Publishers, Inc.. - 9781616687885 ; , s. 3-12
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Bokkapitel (refereegranskat)abstract
- This chapter takes a historical perspective on the emergence of non-linear dynamic modelling in economics. Such models, in particular, involve multistability. In the form of piecewise linearity analysis dates back to the 1930s, with study of fixed point and periodic attractors and their basins. However, even if different cases, depending on different parameter combinations, are studied, no trace of bifurcation analysis can yet be found. Quite early is also business cycle modelling, emerging around 1940, and developed into the nonlinear format around 1950. These models include forces that repel the systems from equilibria/fixed points, but are stabilized through attracting forces far out in the phase space. The resulting trajectories, limit cycles in the case of continuous time models, quasi-periodic orbits in the case of discrete time models, are, however the unique attractors. A certain awareness of Hopf/Neimark bifurcations is there, but, again, there is no explicit study of these. A particular problem for economics as a formal science is that a true study of nonlinear dynamics requires global analysis. Economics, however, has for ages been focused on equilibria and the local study of stability. This is partly due to ideological reasons, as economists preferred convex structures providing for unique equilibrium states, which could be associated with optimality. As a consequence, formal relations are usually described qualitatively, and are seldom stated in explicit form meant to hold over a wide domain of variable values. An exception is provided by production studies, where such production functions were in fact formulated and estimated from time series or panel data. They still provide the best explicit functions to use also in the study of global dynamics even though they were not developed for this purpose.
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| 7. |
- Puu, Tönu, 1936-, et al.
(författare)
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Preface
- 2011
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Ingår i: Nonlinear economic dynamics. - : Nova Science Publishers, Inc.. - 9781616687885
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Bokkapitel (refereegranskat)
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