Fractional catastrophe geometry of rural market percolation: a Koopman-Spectral analysis of socioeconomic complexity in off-season price fluctuations

Authors

  • Claudette Dickmi Vaillam Institut de Recherche Agricole pour le Développement (IRAD), P.O. Box 2123, Yaoundé, Cameroun
  • Asta Lamou Djaligue Institut de Recherche Agricole pour le Développement (IRAD), P.O. Box 2123, Yaoundé, Cameroun

DOI:

https://doi.org/10.21839/jaar.2026.v11.10051

Keywords:

Catastrophe theory, Fractional diffusion, Information geometry, Koopman operator, Percolation/network contagion

Abstract

This article presents a six-layer mathematical framework to model rural off‑season price dynamics as a multi-scale complex system. Layer I formulates stochastic fractional reaction-diffusion-advection PDEs with anisotropic diffusion and multiplicative weather-income noise to capture anomalous spatial transport. Layer II couples regional prices via fractional Brownian motions, yielding fractional Liouville dynamics that encode long‑range temporal dependence. Layer III employs cusp catastrophe theory to characterize abrupt price bifurcations and stream‑tube flow in control‑parameter space. Layer IV uses information geometry (Fisher–Rao metric, KL divergence, heat kernel) to quantify statistical divergence and market proximity on a Riemannian manifold. Layer V applies Koopman operator spectral theory and EDMD to extract modal decompositions and intrinsic mixing timescales. Layer VI frames market connectivity with random geometric graphs and percolation theory, relating giant‑component emergence, critical exponents, and contagion thresholds to systemic risk. Integrating fractional transport, critical transitions, geometric information measures, operator modes, and network percolation explains persistent volatility and systemic contagion in off‑season markets and suggests targeted interventions, namely storage capacity, income stabilization, and connectivity regulation, to mitigate catastrophic price events. Extensions include variable‑order fractional operators, Lévy flight jumps, deep‑Koopman representations, and nonperturbative percolation analysis.

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References

Al-Askar, F. M., Cesarano, C., & Mohammed, W. W. (2023). Effects of the wiener process and beta derivative on the exact solutions of the Kadomtsev–Petviashvili equation. Axioms, 12(8), 748. https://doi.org/10.3390/axioms12080748

Alkhateeb, R., Abu Hammad, M., AL-Shutnawi, B., Laiche, N., & Chikr El Mezouar, Z. (2025). Solving fractional stochastic differential equations via a Bilinear Time-Series framework. Symmetry, 17(5), 764. https://doi.org/10.3390/sym17050764

Alshammari, M., Alshammari, S., Singh, M., Jawarneh, Y., Mohammed, N. M., & Alshammari, K. M. K. (2025). Caputo fractional derivative in the solution of Kolmogorov equations: A new numerical approach. Boundary Value Problems, 2025, 104. https://doi.org/10.1186/s13661-025-02098-4

Amini, A., Vieira, T., & Cotterell, R. (2025). Better estimation of the Kullback—Leibler divergence between language models. arXiv, arXiv:2504.10637. https://doi.org/10.48550/arXiv.2504.10637

Barbu, T., Moşneagu, A.-M., & Tănase, G. (2025). Numerical approximation for a nonlocal and nonlinear reaction–diffusion problem with Robin boundary conditions. Mathematics, 13(21), 3498. https://doi.org/10.3390/math13213498

Baumann, G., & Stenger, F. (2017). Fractional Fokker-Planck equation. Mathematics, 5(1), 12. https://doi.org/10.3390/math5010012

Bin Jebreen, H. (2019). Calculating the weighted Moore–Penrose inverse by a high order iteration scheme. Mathematics, 7(8), 731. https://doi.org/10.3390/math7080731

Borin, D. (2024). Hurst exponent: A method for characterizing dynamical traps. Physical Review E, 110, 064227. https://doi.org/10.1103/PhysRevE.110.064227

Borsellino, V., Schimmenti, E., & El Bilali, H. (2020). Agri-food markets towards sustainable patterns. Sustainability, 12(6), 2193. https://doi.org/10.3390/su12062193

Bravetti, A., García Ariza, M. Á., & Romero-Arias, J. R. (2026). Gradient systems and asymmetric relaxations in view of Riemannian geometry. Entropy, 28(5), 516. https://doi.org/10.3390/e28050516

Brué, E., & Nguyen, Q.-H. (2021). Advection diffusion equations with sobolev velocity field. Communications in Mathematical Physics, 383, 465-487. https://doi.org/10.1007/s00220-021-03993-4

Brüning, J., & Heintze, E. (1984). The asymptotic expansion of Minakshisundaram-Pleijel in the equivariant case. Duke Mathematical Journal, 51(4), 959-980. https://doi.org/10.1215/S0012-7094-84-05143-3

Bytsenko, A. A., & Williams, F. L. (1999). Asymptotics of the heat kernel on rank-1 locally symmetric spaces. Journal of Physics A: Mathematical and General, 32(31), 5773-5779. https://doi.org/10.1088/0305-4470/32/31/303

Can, Z., & Tekin, P. (2026). Comparative results for αi-curvature conditions on Kenmotsu manifolds via the Levi-Civita and Schouten–van Kampen connections. Symmetry, 18(3), 473. https://doi.org/10.3390/sym18030473

Cheng, B., & Tong, H. (2026a). An approach to Fisher-Rao metric for infinite dimensional non-parametric information geometry. Entropy, 28(4), 374. https://doi.org/10.3390/e28040374

Cheng, B., & Tong, H. (2026b). An approach to Fisher-Rao metric for infinite dimensional non-parametric information geometry. arXiv, arXiv:2512.21451. https://doi.org/10.48550/arXiv.2512.21451

Choi, N., Cho, H., & Lee, B. (2019). Development of Floquet multiplier estimator to determine nonlinear oscillatory behavior in power system data measurement. Energies, 12(10), 1824. https://doi.org/10.3390/en12101824

Colbrook, M. J., Drmač, Z., & Horning, A. (2025). An Introductory guide to Koopman learning. arXiv, arXiv:2510.22002. https://doi.org/10.48550/arXiv.2510.22002

Colin de Verdière, Y., Hillairet, L., & Trélat, E. (2021). Small-time asymptotics of hypoelliptic heat kernels near the diagonal, nilpotentization and related results. Annales Henri Lebesgue, 4, 897-971. https://doi.org/10.5802/ahl.93

Constantin, P., & Foias, C. (1985). Global Lyapunov exponents, Kaplan-Yorke formulas and the dimension of the attractors for 2D Navier-Stokes equations. Communications in Pure Applied Mathematics, 38, 1-27.

Durán-Olivencia, M. A. (2026). The emergence of socio-economic structure: A first-principles kinetic theory. Journal of Statistical Mechanics: Theory and Experiment, 2026(4), 043205. https://doi.org/10.1088/1742-5468/ae5c8d

El Aroudi, A., Cañas-Estrada, N., Debbat, M., & Al-Numay, M. (2021). Nonlinear dynamics and stability analysis of a three-cell flying capacitor DC-DC converter. Applied Sciences, 11(4), 1395. https://doi.org/10.3390/app11041395

El-Sayed, A. M. A., & Fouad, H. A. (2021). On a coupled system of stochastic ito^-differential and the arbitrary (fractional) order differential equations with nonlocal random and stochastic integral conditions. Mathematics, 9(20), 2571. https://doi.org/10.3390/math9202571

Engelke, S., Naveau, P., & Zhou, C. (2026). A Kullback-Leibler divergence test for multivariate extremes: Theory and practice. arXiv, arXiv:2602.02316. https://doi.org/10.48550/arXiv.2602.02316

Farouk, F. T., Tawfik, A. N., Tarabia, F. S., & Maher, M. (2023). On possible minimal length deformation of metric tensor, Levi-Civita connection, and the Riemann curvature tensor. Physics, 5(4), 983-1002. https://doi.org/10.3390/physics5040064

Grech, C., Buzio, M., Pentella, M., & Sammut, N. (2020). Dynamic ferromagnetic hysteresis modelling using a Preisach-Recurrent neural network model. Materials, 13(11), 2561. https://doi.org/10.3390/ma13112561

Hamza, A. E., Seghier, M., Maazouz, K., Bellabes, Z., Moumen, A., & Bouye, M. (2026). Coupled system of variable-order fractional differential equations. Fractal and Fractional, 10(5), 305. https://doi.org/10.3390/fractalfract10050305

Huang, H. (2026). A new index for quantifying the statistical difference between two probability distributions. Axioms, 15(2), 150. https://doi.org/10.3390/axioms15020150

Jalali Mojahed, A., Moattar, M. H., & Ghaffari, H. (2024). Supervised density-based metric learning based on Bhattacharya distance for imbalanced data classification problems. Big Data and Cognitive Computing, 8(9), 109. https://doi.org/10.3390/bdcc8090109

Kadkhoda, N., Lashkarian, E., Inc, M., Akinlar, M. A., & Chu, Y.-M. (2020). new exact solutions and conservation laws to the fractional-order Fokker–Planck equations. Symmetry, 12(8), 1282. https://doi.org/10.3390/sym12081282

Kazemi, M., Yaghoobnia, A., Moghaddam, B. P., & Galhano, A. (2025). Analytical and computational investigations of stochastic functional integral equations: Solution existence and Euler–Karhunen–Loève simulation. Mathematics, 13(3), 427. https://doi.org/10.3390/math13030427

Kengne, E. R. M., Kammogne, A. S. T., Siewe, M. S., Tamo, T. T., Azar, A. T., Mahlous, A. R., Tounsi, M., & Khan, Z. I. (2023). Bifurcation analysis of a photovoltaic power source interfacing a current-mode-controlled boost converter with limited current sensor bandwidth for maximum power point tracking. Sustainability, 15(7), 6097. https://doi.org/10.3390/su15076097

Kober, V., Makovetskii, A., & Voronin, S. (2025). Karhunen–Loève Expansion using a parametric model of oscillating covariance function. Mathematics, 13(16), 2569. https://doi.org/10.3390/math13162569

Koch, S., & Neuenkirch, A. (2019). The Mandelbrot-van Ness fractional Brownian motion is infinitely differentiable with respect to its Hurst parameter. Discrete and Continuous Dynamical Systems - B, 24(8), 3865-3880. https://doi.org/10.3934/dcdsb.2018334

Koleva, M. N. (2026). A numerical approach for the simultaneous identification of a source term and a Robin boundary coefficient in time-fractional Reaction–Diffusion equations. Mathematics, 14(2), 324. https://doi.org/10.3390/math14020324

Kolonitskii, S. B., Lerman, L. M., & Nazarov, A. I. (2024). Entire solutions to the Swift—Hohenberg equation via variational approach. arXiv, arXiv:2404.05066. https://doi.org/10.48550/arXiv.2404.05066

Kumar, A., Jaiswal, D. K., & Kumar, N. (2009). Analytical solutions of one-dimensional advection-diffusion equation with variable coefficients in a finite domain. Journal of Earth System Science, 118(5), 539-549. https://doi.org/10.1007/s12040-009-0049-y

Lawler, G. F. (2007). Schramm-Loewner Evolution. arXiv, arXiv:0712.3256. https://doi.org/10.48550/arXiv.0712.3256

Liang, T., Poggio, T., Rakhlin, A., & Stokes, J. (2019). Fisher-Rao metric, geometry, and complexity of neural networks. arXiv, arXiv:1711.01530. https://doi.org/10.48550/arXiv.1711.01530

Lischke, A., Pang, G., Gulian, M., Song, F., Glusa, C., Zheng, X., Mao, Z., Cai, W., Meerschaert, M. M., Ainsworth, M., & Karniadakis, G. E. (2019). What is the fractional Laplacian? arXiv, arXiv:1801.09767. https://doi.org/10.48550/arXiv.1801.09767

Liu, C.-S., Kuo, C.-L., & Chang, C.-W. (2024). Matrix pencil optimal iterative algorithms and restarted versions for linear matrix equation and pseudoinverse. Mathematics, 12(11), 1761. https://doi.org/10.3390/math12111761

Lu, Q., Wang, L., Li, F., Yang, Y., Liu, Q., Wang, X., Chi, F., Liu, L., & Yi, Z. (2026). An electrohydrodynamic phase-field model for contact angle hysteresis in electrowetting pixels: Decoupling physical pinning and charge trapping. Micromachines, 17(4), 480. https://doi.org/10.3390/mi17040480

Luo, W. (2026). The Moore–Penrose inverse and product decomposition of idempotent operators on Hilbert C*-modules. Axioms, 15(2), 141. https://doi.org/10.3390/axioms15020141

Mahmoud, E. I., & Orlov, V. N. (2021). Numerical solution of two dimensional time-space fractional Fokker Planck equation with variable coefficients. Mathematics, 9(11), 1260. https://doi.org/10.3390/math9111260

Maier, B. F. (2019). Generalization of the small-world effect on a model approaching the Erdős-Rényi random graph. Scientific Reports, 9(1), 9268. https://doi.org/10.1038/s41598-019-45576-3

Manev, H. (2023). First natural connection on Riemannian Π-Manifolds. Mathematics, 11(5), 1146. https://doi.org/10.3390/math11051146

Matthies, H. G. (2025). Reduced-order models and conditional expectation: Analysing parametric low-order approximations. Computation, 13(2), 58. https://doi.org/10.3390/computation13020058

Medvedev, G. S., & Pelinovsky, D. E. (2023). Turing bifurcation in the Swift-Hohenberg equation on deterministic and random graphs. arXiv, arXiv:2312.10207. https://doi.org/10.48550/arXiv.2312.10207

Merenda, J. V., & Bruno, O. M. (2023). Using deterministic tourist walk as a small-world metric on Watts-Strogatz networks. Physica A: Statistical Mechanics and Its Applications, 621, 128713. https://doi.org/10.1016/j.physa.2023.128713

Mezić, I., Cortés, J., Worthmann, K., Lazar, M., & Lederer, A. (2026). Koopman operator theory: Fundamentals, control, and applications. arXiv, arXiv:2607.01819. https://doi.org/10.48550/arXiv.2607.01819

Mofarreh, F., Khan, A., Shah, R., & Abdeljabbar, A. (2023). A comparative analysis of fractional-order Fokker–Planck equation. Symmetry, 15(2), 430. https://doi.org/10.3390/sym15020430

Mohammed, M. (2022). Well-posedness for nonlinear parabolic stochastic differential equations with nonlinear robin conditions. Symmetry, 14(8), 1722. https://doi.org/10.3390/sym14081722

Mohammed, W. W., Al-Askar, F. M., Cesarano, C., Botmart, T., & El-Morshedy, M. (2022). Wiener process effects on the solutions of the fractional (2 + 1)-dimensional Heisenberg ferromagnetic spin chain equation. Mathematics, 10(12), 2043. https://doi.org/10.3390/math10122043

Monteiro, R., & Yoshinaga, N. (2020). The Swift–Hohenberg equation under Directional-Quenching: finding heteroclinic connections using spatial and spectral decompositions. Archive for Rational Mechanics and Analysis, 235(1), 405-470. https://doi.org/10.1007/s00205-019-01427-z

Morales, R., Matteo, T. D., Gramatica, R., & Aste, T. (2012). Dynamical Hurst exponent as a tool to monitor unstable periods in financial time series. Physica A: Statistical Mechanics and Its Applications, 391(11), 3180-3189. https://doi.org/10.1016/j.physa.2012.01.004

Morgan, D., & Dawes, J. H. P. (2014). The Swift-Hohenberg equation with a nonlocal nonlinearity. Physica D: Nonlinear Phenomena, 270, 60-80. https://doi.org/10.1016/j.physd.2013.11.018

Nichols, J. M., Todd, M. D., Seaver, M., Trickey, S. T., Pecora, L. M., & Moniz, L. (2003). Controlling system dimension: A class of real systems that obey the Kaplan–Yorke conjecture. Proceedings of the National Academy of Sciences of the United States of America, 100(26), 15299-15303. https://doi.org/10.1073/pnas.2535197100

Nielsen, F. (2014). Generalized Bhattacharyya and Chernoff upper bounds on Bayes error using quasi-arithmetic means. Pattern Recognition Letters, 42, 25-34. https://doi.org/10.1016/j.patrec.2014.01.002

Nielsen, F. (2024). Approximation and bounding techniques for the Fisher-Rao distances between parametric statistical models. In A. S. R. Srinivasa Rao (Ed.), Handbook of Statistics (Vol. 51, pp. 67-116). Elsevier. https://doi.org/10.1016/bs.host.2024.06.003

Patyn, C., & Deconinck, G. (2024). A concise introduction to Koopman operator theory and the extended dynamic mode decomposition. arXiv, arXiv:2410.02766. https://doi.org/10.48550/arXiv.2410.02766

Pirozzi, E. (2024). Some fractional stochastic models for neuronal activity with different time-scales and correlated inputs. Fractal and Fractional, 8(1), 57. https://doi.org/10.3390/fractalfract8010057

Rysbaiuly, B., Sinitsa, A., & Capsoni, A. (2022). Analytical inverse analysis methodological approach for thermo-physical parameters estimation of multilayered medium terrain with homogenized sampled measurements. Symmetry, 14(11), 2248. https://doi.org/10.3390/sym14112248

Shlens, J. (2014). Notes on Kullback-Leibler divergence and likelihood. arXiv, arXiv:1404.2000. https://doi.org/10.48550/arXiv.1404.2000

Sidaoui, R., Alfedeel, A. H. A., Ahmad, J., Aldwoah, K., Ali, A., Osman, O., & Tedjani, A. H. (2025). Mathematical perspectives of a coupled system of nonlinear hybrid stochastic fractional differential equations. Fractal and Fractional, 9(10), 622. https://doi.org/10.3390/fractalfract9100622

Song, H. F., & Wang, X.-J. (2014). A simple, distance-dependent formulation of the Watts-Strogatz model for directed and undirected small-world networks. Physical Review E, 90(6), 062801. https://doi.org/10.1103/PhysRevE.90.062801

Stanojević, V., Kazakovtsev, L., Stanimirović, P. S., Rezova, N., & Shkaberina, G. (2022). Calculating the Moore–Penrose generalized inverse on massively parallel systems. Algorithms, 15(10), 348. https://doi.org/10.3390/a15100348

Stempin, P., & Sumelka, W. (2025). Approximation of fractional caputo derivative of variable order and variable terminals with application to initial/boundary value problems. Fractal and Fractional, 9(5), 269. https://doi.org/10.3390/fractalfract9050269

Subramanian, C. S., Dye, M., & Redkar, S. (2020). Dynamic analysis of suction stabilized floating platforms. Journal of Marine Science and Engineering, 8(8), 587. https://doi.org/10.3390/jmse8080587

Teymurazyan, R. (2023). The fractional Laplacian: A primer. arXiv, arXiv:2310.19118. https://doi.org/10.48550/arXiv.2310.19118

Theresia, A., Ikhsan, M., Kacaribu, F. N., & Sumarto, S. (2025). Spillover effect of food producer price volatility in Indonesia. Economies, 13(9), 256. https://doi.org/10.3390/economies13090256

Tsuruyama, T. (2025). Kullback-Leibler divergence as a measure of irreversible information loss near black hole horizons. The European Physical Journal Plus, 140(6), 588. https://doi.org/10.1140/epjp/s13360-025-06500-z

Tu, F., Hu, S., Zhuang, Y., Lv, J., Wang, Y., & Sun, Z. (2016). Hysteresis curve fitting optimization of magnetic controlled shape memory alloy actuator. Actuators, 5(4), 25. https://doi.org/10.3390/act5040025

Tu, H., Wang, X., & Li, Y. (2025). Handling multi-source uncertainty in accelerated degradation through a Wiener-based robust modeling scheme. Sensors, 25(21), 6654. https://doi.org/10.3390/s25216654

Uzel, G., Kuzu, M., Güler, A., & Gürlük, S. (2025). Asymmetric effects of agricultural input prices on farmgate prices in Türkiye. Agriculture, 15(6), 607. https://doi.org/10.3390/agriculture15060607

Van Mieghem, P. (2022). Origin of the fractional derivative and fractional non-Markovian continuous-time processes. Physical Review Research, 4(2), 023242. https://doi.org/10.1103/PhysRevResearch.4.023242

Wada, T., & Scarfone, A. M. (2026). Non-metricity in information geometry. Entropy, 28(4), 447. https://doi.org/10.3390/e28040447

Wang, F., Liu, W., Zhang, K., He, Y., Qi, K., Tang, Y., & Di, Z. (2026a). Third-order transitions in Ising and Potts models on Watts—Strogatz small-world networks. arXiv, arXiv:2603.11522. https://doi.org/10.48550/arXiv.2603.11522

Wang, J., Xu, J., Hao, Y., Huo, L., Wang, Z., & Li, B. (2026b). Anisotropic total generalized variation enhanced deep image prior for image denoising. Symmetry, 18(3), 452. https://doi.org/10.3390/sym18030452

Washburn, J., Zlatanović, M., & Beltracchi, P. (2026). Multidimensional cost geometry. Axioms, 15(5), 378. https://doi.org/10.3390/axioms15050378

Zhang, H.-Y., Feng, Z.-Q., Feng, S.-Y., & Zhou, Y. (2024). Typical algorithms for estimating Hurst exponent of time sequence: A data analyst’s perspective. IEEE Access, 12, 185528-185556. https://doi.org/10.1109/ACCESS.2024.3512542

Zhao, H., Wang, F., Zhang, Y., Zheng, Z., Ma, J., & Fu, C. (2024). Fractional-order modeling and stochastic dynamics analysis of a nonlinear rubbing overhung rotor system. Fractal and Fractional, 8(11), 643. https://doi.org/10.3390/fractalfract8110643

Zheng, X., Ervin, V. J., & Wang, H. (2024). A generalized fractional Laplacian. arXiv, arXiv:2304.12419. https://doi.org/10.48550/arXiv.2304.12419

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09-10-2026

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