Kwaśniewski’s cobweb posets uniquely represented by directed acyclic graphs are such a generalization of the Fibonacci tree that allows joint combinatorial interpretation for all of them under admissibility condition. This interpretation was derived in the source papers and it entailes natural enquieres already formulated therein. In our note we response to one of those problems. This is a tili...

The cobweb model of competitive market dynamics has been examined in the form of system dynamics model. The classical formulation of the cobweb demand-supply model has been transformed in the set of equations suitable for system dynamics modelling. The model has been expanded by the time parameter ∆t which enables the stability analysis of the model for the change in the ∆t. The structure of th...

This study augments the traditional linear cobweb model with lower and upper bounds for variations of output. Its purpose is to detect the relationship between the output constraints and the dynamics of the modified model. Due to the upper and lower bounds, a transitional function takes on a tilted z-profile having three piecewise segments with two turning points. It prevents the price (or quan...

We consider the problem of two-point resistance in a resistor network previously studied by one of us (Wu 2004 J. Phys. A: Math. Gen. 37 6653). By formulating the problem differently, we obtain a new expression for the two-point resistance between two arbitrary nodes which is simpler and can be easier to use in practice. We apply the new formulation to the cobweb resistor network to obtain the ...

This paper explores the extent to which the lack of rationality of economic agents has affected the economic fluctuations and the social welfare of the U.S. hog market. A group of articles has ascribed the business cycles of the hog market, observed by economists as early as the last century, mainly to the lack of rationality (cobweb expectations) of economic agents. In contrast, others, assumi...

In this paper we present an unsupervised learning algorithm for incremental concept formation, based on an augmented version of COBWEB. The algorithm is applied to the task of acquiring a verb taxonomy through the systematic observation of verb usages in corpora. Using a Machine Learning methodology for a Natural language problem required adjustments on both sides. In fact, concept formation al...

a r t i c l e i n f o According to empirical studies, speculators place significant orders in commodity markets and may cause bubbles and crashes. This paper develops a cobweb-like commodity market model that takes into account the behavior of technical and fundamental speculators. We show that interactions between consumers, producers and heterogeneous speculators may produce price dynamics wh...

Cladobotryum dendroides (= Dactylium dendroides) has hitherto been regarded as the major causal agent of cobweb disease of the cultivated mushroom, Agaricus bisporus. Nucleotide sequence data for the internal transcribed spacer (ITS) regions of four Cladobotryum/Hypomyces species reported to be associated with cobweb disease, however, indicate that the most common pathogen is now C. mycophilum....