Vertical diversity and equilbrium growth

This paper examines the effect of an increase in vertical diversity in workers' skill on the long run growth rate of an economy. It uses a two-secror model where the techonology of the consumption-good sector is supermodular and that of the R&D sector is submodular. By adopting Grossman and Maggi's(2000) model to a framework of growth based on R&D, it shows first that diversity is condutive to growth. As the main innovation, communication gap is introduced among workers. It is then shown that growth may not be increasing with diversity. There may be an inverse-U shaped relationship.Diversity, talent distribution, supermodular technology, submodular technology, growth, skill, R&D, innovations

Endogenous Distribution, Politics and Growth

This paper generalizes the analysis of distributive conflict, politics, and growth developed by by Alesina-Rodrik (1994). We construct a heterogenous-agent framework in which both growth and the distribution of wealth are endogenous. Due to adjustments in the distribution of wealth, the composition of factor ownership across households equalizes in the long run. This implies that the optimal tax rate is the same for all households and equals the growth maximizing tax rate. Hence, there is no distributive conflict in the long run. When the model is augmented with a non-political redistributive policy, the model predicts that long run growth exhibits a negative monotonic relationship with respect to this policy, i.e., a redistributive policy that leads to a more equitable wealth distribution unambiguously reduces growth in the long run.Median Voter, Endogenous Growth, Wealth Distribution, Distributive Conflict, Redistributive Policy.

Endogenous distribution, politics and the growth-equity tradeoff

In comparison to the standard literature on inequality and growth which assumes the former to be exogenous, we formulate a model in which inequality and growth are both endogenous. Furthermore, long-run distribution, at least locally, is shown to be independent of the initial distribution of factor ownership. It is shown that exogenous policy changes that are primarily targeted towards growth and foster less inequality do enhance growth. But those that are primarily redistributive and imply more equal distribution reduce growth. This is consistent with recent empirical work which shows that inequality and growth may be positively related.Median Voter, Endogenous Growth, Wealth Distribution, Distributive Conflict, Redistributive Policy

Endogenous trading bloc formation in a North-South global economy

Majority of the trading blocs to date are between similar countries, rather than between developed and developing countries. This paper provides a rationale for why trading blocs among similar countries may arise as an equilibrium phenomenon. It develops a model of an asymmetric world economy, in which there are at least four countries. The countries are differentiated with respect to their market size and market structure.

Persistence of a Rouse polymer chain under transverse shear flow

We consider a single Rouse polymer chain in two dimensions in presence of a transverse shear flow along the $x$ direction and calculate the persistence probability $P_0(t)$ that the $x$ coordinate of a bead in the bulk of the chain does not return to its initial position up to time $t$. We show that the persistence decays at late times as a power law, $P_0(t)\sim t^{-\theta}$ with a nontrivial exponent $\theta$. The analytical estimate of $\theta=0.359...$ obtained using an independent interval approximation is in excellent agreement with the numerical value $\theta\approx 0.360\pm 0.001$.Comment: 6 page

Deterrence, preemption and panic: A Common-enemy problem of terrorism

We develop a game-theoretic analysis of terrorism that examines the interaction between a terrorist organization and multiple target countries, and considers both pre-emption and deterrence as counterterrorist policies. The damage from terror includes not only the material cost of fatality, injury and loss of property, but also the resultant fear. The fear-effect leads to different kinds of equilibria and implications for counter-terrorism policies. In particular, the model identifies conditions under which greater pre-emption may be the rational response to an increase in terrorism, i.e., it analyzes the merit of the dictum: "offense is the best defense." Further, it examines the characteristics of cooperative behavior among target countries in dealing with the threat of terrorism.Terrorism; Preemption; Panic; Deterrence; Cooperation; Target Countries

Landau theory of glassy dynamics

An exact solution of a Landau model of an order-disorder transition with activated critical dynamics is presented. The model describes a funnel-shaped topography of the order parameter space in which the number of energy lowering trajectories rapidly diminishes as the ordered ground-state is approached. This leads to an asymmetry in the effective transition rates which results in a non-exponential relaxation of the order-parameter fluctuations and a Vogel-Fulcher-Tammann divergence of the relaxation times, typical of a glass transition. We argue that the Landau model provides a general framework for studying glassy dynamics in a variety of systems.Comment: 4 pages, 2 figure

Multi-item a supply chain production inventory model of time dependent production rate and demand rate under space constraint in fuzzy environment

In this paper, we have developed an integrated production inventory model for two echelon supply chain consisting of one vendor and one retailer. Production rate and demand rate of retailer and customer are time dependent. Idle time cost of the vendor has been considered. Multi-item inventory has been considered. In integrated inventory model average cost has been calculated under limitation on stroge space. Two echelon supply chain fuzzy inventory model has been solved by various techniques like as Fuzzy programming technique with hyperbolic membership functions (FPTHMF), Fuzzy non-linear programming technique (FNLP) and Fuzzy additive goal programming technique (FAGP),  weighted Fuzzy non-linear programming technique (WFNLP) and weighted Fuzzy additive goal programming technique (WFAGP). A numerical example is illustrated to test the model. Finally to make the model more realistic, sensitivity analysis has been shown

Multi objective fuzzy inventory model with deterioration, price and time dependent demand and time dependent holding cost

In this paper, we have formulated an inventory model with time dependent holding cost, selling price as well as time dependent demand. Multi-item inventory model has been considered under limitation on storage space. Due to uncertainty all the require cost parameters are taken as generalized trapezoidal fuzzy number. Our proposed multi-objective inventory model has been solved by using fuzzy programming techniques which are FNLP, FAGP, WFNLP and WFAGP methods. A numerical example is provided to demonstrate the application of the model. Finally to illustrate the model and sensitivity analysis and graphical representation have been shown.