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Barbora Volná

Publications and source records attributed to Barbora Volná.

8 recordsLinked to original sources

Comparison of Phase-Plane and Trend-Based Qualitative Analysis of a Dynamic Two-Dimensional IS--LM Model

We compare the classical phase-plane analysis of a dynamic two-dimensional IS--LM model with a sign-based trend approach. Applying both methods to the same specification, we examine which qualitative properties of the system can be established solely from sign relations and how these methods can complement each other. In summary, these two approaches capture complementary perspectives on the qualitative behaviour of the considered model, combining the detailed local classification of equilibrium dynamics provided by phase-plane analysis with the broader admissible qualitative structures captured by trend-based analysis.

math.DS

Optimisation of complex product innovation processes based on trend models with three-valued logic

This paper investigates complex product-innovation processes using models grounded in a set of heuristics. Each heuristic is expressed through simple trends -- increasing, decreasing, or constant -- which serve as minimally information-intensive quantifiers, avoiding reliance on numerical values or rough sets. A solution to a trend model is defined as a set of scenarios with possible transitions between them, represented by a transition graph. Any possible future or past behaviour of the system under study can thus be depicted by a path within this graph.

cs.AI

Information-Nonintensive Models of Rumour Impacts on Complex Investment Decisions

This paper develops a qualitative framework for analysing the impact of rumours on complex investment decisions (CID) under severe information constraints. The proposed trend-based models rely on minimal data inputs in the form of increasing, decreasing, or constant relations. Sets of trend rules generate scenarios, and permitted transitions between them form a directed graph that represents system behaviour over time. The approach is applied in three interconnected models: financial CID, rumour-spreading dynamics, and their integration.

econ.GN

SME Gender-Related Innovation: A Non-Numerical Trend Analysis Using Positive, Zero, and Negative Quantities

This paper addresses gender-related aspects of innovation processes in Small and Medium Enterprises (SMEs). Classical analytical and statistical approaches often struggle with the high complexity and insufficient data typical of gender-related innovation studies. We propose a trend-based modelling framework that requires minimal information and uses non-numerical quantifiers: increasing, constant, and decreasing. This approach enables the analysis of ten-dimensional models including variables such as Gender, Product Innovation, Process Innovation, and High-Risk Tolerance. Using trend-based artificial intelligence methods, we identify 13 distinct scenarios and all possible transitions between them. This allows for the evaluation of queries like: Can exports increase while gender parameters remain constant? Two versions of the GASI trend model are presented: the original and an expert-modified version addressing critiques related to scenario transitions. The final model confirms stability and supports the assumption that "no tree grows to heaven." Trend-based modelling offers a practical, interpretable alternative for complex, data-scarce systems.

econ.GN

On chaotic sets of solutions for a class of differential inclusions on $\mathbb{R}^2$

We deal with a set of solutions of the continuous multi-valued dynamical systems on $\mathbb{R}^2$ of the form $\dot x \in F(x)$ where $F(x)$ is a set-valued function and $F=\{f_1,f_2\}$. Such dynamical systems are frequently used in mathematical economics. We rectify the sufficient conditions for a set of solutions of this system to exhibit Devaney chaos, $ω$-chaos and infinite topological entropy from: B.R. Raines, D.R. Stockman, Fixed points imply chaos for a class of differential inclusions that arise in economic models, Trans. American Math. Society 364 (5) (2012), 2479--2492. We significantly improve their results. At the end, we illustrate these problems on our own macroeconomic model.

math.DS

Can we explain unexpected fluctuations of long-term real interest rate?

In this paper, we present own point of view how the unexpected fluctuations of the long-term real interest rate can be explained. We describe a macroeconomic environment by the modification of the fundamental macroeconomic equilibrium model called the IS-LM model. Last but not least, we suggest a possible cooperation between the fiscal and monetary policy to reduce these fluctuations. Our modelling is demonstrated on an illustrative example.

q-fin.GN

Existence of Chaos in Plane $\mathbb{R}^2$ and its Application in Macroeconomics

The Devaney, Li-Yorke and distributional chaos in plane $\mathbb{R}^2$ can occur in the continuous dynamical system generated by Euler equation branching. Euler equation branching is a type of differential inclusion $\dot x \in \{f(x),g(x) \} $, where $f,g:X \subset \mathbb{R}^n \rightarrow \mathbb{R}^n$ are continuous and $f(x) \neq g(x)$ in every point $x \in X$. Stockman and Raines (Stockman, D. R.; Raines, B. R.: Chaotic sets and Euler equation branching, Journal of Mathematical Economics, 2010, Volume 46, pp. 1173-1193) defined so-called chaotic set in plane $\mathbb{R}^2$ which existence leads to an existence of Devaney, Li-Yorke and distributional chaos. In this paper, we follow up on Stockman, Raines and we show that chaos in plane $\mathbb{R}^2$ with two "classical" (with non-zero determinant of Jacobi's matrix) hyperbolic singular points of both branches not lying in the same point in $\mathbb{R}^2$ is always admitted. But the chaos existence is caused also by set of solutions of Euler equation branching which have to fulfil conditions following from the definition of so-called chaotic set. So, we research this set of solutions. In the second part we create new overall macroeconomic equilibrium model called IS-LM/QY-ML. The construction of this model follows from the fundamental macroeconomic equilibrium model called IS-LM but we include every important economic phenomena like inflation effect, endogenous money supply, economic cycle etc. in contrast with the original IS-LM model. We research the dynamical behaviour of this new IS-LM/QY-ML model and show when a chaos exists with relevant economic interpretation.

math.DS

Relaxation Oscillations in New IS-LM Model

In this paper, we create new version of IS-LM model. The original IS-LM model has two main deficiencies: assumptions of constant price level and of strictly exogenous money supply. New IS-LM model eliminates these deficiencies. In the second section, we prove the existence of relaxation oscillations in this new IS-LM model.

math.DS