The Range‐Resident Logistic Model: A New Framework to Formalise the Population‐Dynamics Consequences of Range Residency

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ABSTRACTIndividual movement is critical in shaping population dynamics. However, existing frameworks linking these two processes often rely on unrealistic assumptions or numerical simulations. To address this gap, we introduce the range‐resident logistic model, an easy‐to‐simulate and mathematically tractable extension of the spatial logistic model that incorporates empirically supported range‐resident movement. Our framework unifies non‐spatial and (sessile) spatial formulations of the logistic model as limiting cases. Between these regimes, the long‐term population size depends nonlinearly on home‐range size and spatial distribution. Neglecting range residency can hence lead to under‐ or overestimating population carrying capacity. To better understand these results, we also introduce a novel crowding index that depends on movement parameters and can be estimated from tracking data. This index captures the influence of spatial structure on population size, and serves as a robust predictor of abundance. The range‐resident logistic model is thus a unifying framework bridging movement and population ecology.

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Propensity score can be described as a probability of certain treatments conditional to the given observed covariates. Propensity score is one of the known methods to allows an observational study emulating certain characteristics from that of a randomized trial. The most common method used to estimate this score is the logistic regression model. Logistic regression can be used to model the probability of a certain event. With the advancement that is happening to spatial statistics, one can also build a logistic regression model that takes into consideration to that of spatial dependence. Thus, accommodate the spatial effect that is likely happening on observation data that came from different places. Problem arises from this model, that is the estimation of the parameters on the spatial logistic model. EM algorithm which is needed for this problem, still requires another adjustment since the expectation in the E-step is not available in closed form. Variational method modification is then proposed as an alternative for this problem. This paper reviews the propensity score estimation using spatial logistic regression and discusses the variational method as an alternative method to tackle the problem in estimating the parameters on the spatial logistic regression model in a theoretical study.

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The logistic model has long been used in ecological modelling for its simplicity and effectiveness. Variations on the logistic model are prolific but, to date, there are a limited number of models that incorporate the stochastic nature of the carrying capacity. This study proposes a modification to the logistic model to incorporate a second differential equation which describes the changes in the carrying capacity, thus treating the carrying capacity as a state variable. The carrying capacity is modelled via a stochastic differential equation that accounts for stochastic ('noisy') variations in the finite resources that the population relies on. The extinction probability distribution, expected solution paths, variance of the solution paths, and distribution of the population are computed using the Monte Carlo method. References R. B. Banks. Growth and Diffusion Phenomena . Springer, 1994. doi:10.1007/978-3-662-03052-3 F. Brauer and C. Castillo-Chavez. Mathematical Models in Population Biology and Epidemiology . Springer, 2001. doi:10.1007/978-1-4614-1686-9 A. Tsoularis and J. Wallace. Analysis of logistic growth models. Math. Biosci. , 179:21–55, 2002. doi:10.1016/S0025-5564(02)00096-2 S. Oppel, G. Hilton, N. Ratcliffe, C. Fenton, J. Daley, G. Gray, J. Vickery and D. Gibbons. Assessing population viability while accounting for demographic and environmental uncertainty. Ecology , 95:1809–1818, 2014. doi:10.1890/13-0733.1 J. E. Cohen. Population growth and earth's human carrying capacity. Science , 269:341–346 1995. doi:10.1126/science.7618100 J. M. Cushing. Periodic time-dependent predator-prey systems. SIAM J. Appl. Math. , 32:82–95 1977. doi:10.1137/0132006 B. D. Coleman. Nonautonomous logistic equation as models of the adjustment of populations to environmental change. Math. Biosci. , 45:159–173, 1979. doi:10.1016/0025-5564(79)90057-9 J. Vandermeer. Seasonal ioschronic forcing of Lotka Volterra equations. Prog. Theor. Phys. , 96:13–28, 1996. doi:10.1143/PTP.96.13 H. M. Safuan, Z. Jovanoski, I. N. Towers and H. S. Sidhu. Exact solution of a non-autonomous logistic population model. Ecol. Model. , 251:99–102, 2013. doi:10.1016/j.ecolmodel.2012.12.016 P. Del Monte-Luna, B. W. Brook, M. J. Zetina-Rejon and V. H. Cruz-Escalona. The carrying capacity of ecosystems. Global Ecol. Biogeogr. , 13:485–495, 2004. doi:10.1111/j.1466-822X.2004.00131.x H. Safuan, I. N. Towers, Z. Jovanoski and H. S. Sidhu. A simple model for the total microbial biomass under occlusion of healthy human skin. 19th International Congress on Modelling and Simulation , Perth, Australia, December 2011, 733–739. http://mssanz.org.au/modsim2011/AA/safuan.pdf H. M. Safuan, I. N. Towers, Z. Jovanoski and H. S. Sidhu. Coupled logistic carrying capacity model. EMAC2011, ANZIAM J. , 53:C172–C184 2012. http://journal.austms.org.au/ojs/index.php/ANZIAMJ/article/view/4972 H. M. Safuan, H. S. Sidhu, Z. Jovanoski and I. N. Towers. Impacts of biotic resource enrichment on predator-prey population. B. Math. Biol. , 75:1798–1812, 2013. doi:10.1007/s11538-013-9869-7 H. M. Safuan, H. S. Sidhu, Z. Jovanoski and I. N. Towers. A two-species predator-prey model in an environment enriched by a biotic resource. CTAC2012, ANZIAM J. , 54:C768–C787, 2014 . http://journal.austms.org.au/ojs/index.php/ANZIAMJ/article/view/6376 S. M. Henson and J. M. Cushing. The effect of periodic habitat fluctuations on a nonlinear insect population model. J. Math. Biol. , 36:201–226, 1997. doi:10.1007/s002850050098 V. Mendez, I. Llopis, D. Campos and W. Horsthemke. Extinction conditions for isolated populations affected by environmental stochasticity. Theor. Popul. Biol. , 77:250–256, 2010. doi:10.1016/j.tpb.2010.02.006 P. Foley. Predicting extinction times from environmental stochasticity and carrying capacity. Conserv. Biol. , 8:124–137, 1994. http://www.jstor.org/stable/2386727 D. J. Higham. An algorithmic introduction to numerical simulation of stochastic differential equations. SIAM Rev. , 43:525–546, 2001. doi:10.1137/S0036144500378302 C. W. Gardiner. Handbook of Stochastic Methods , 2nd ed. Springer, 1985. http://trove.nla.gov.au/version/46588286

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Statistical Analysis of Ecological Mathematical Model Based on Differential Equation
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  • 10.1007/s00477-012-0620-y
Modeling determinants of urban growth in Dongguan, China: a spatial logistic approach
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  • Stochastic Environmental Research and Risk Assessment
  • Felix H F Liao + 1 more

This paper examines spatial variations of urban growth patterns in Chinese cities through a case study of Dongguan, a rapidly industrializing city characterized by a bottom-up pattern of development based on townships. We have employed both non-spatial and spatial logistic regression models to analyze urban land conversion. The non-spatial logistic regression has found the significance of accessibility, neighborhood conditions and socioeconomic factors for urban development. The logistic regression with spatially expanded coefficients significantly improves the orthodoxy logistic regression with lower levels of spatial autocorrelation of residuals and better goodness-of-fit. More importantly, the spatial logistic model reveals the spatially varying relationship between urban growth and its underlying factors, particularly the local influence of environment protection and urban development policies. The results of the spatial logistic model also provide clear clues for assessing environmental risks to take the local contexts into account.

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MODEL LOGISTIK FUZZY DENGAN ADANYA PEMANENAN PROPORSIONAL
  • Jun 22, 2022
  • EPSILON: JURNAL MATEMATIKA MURNI DAN TERAPAN
  • Fitri Nor Annisa + 2 more

The logistic growth model with proportional harvesting is a population growth model that takes into account harvesting factors. In real life, not all conditions can be known with certainty, such as different growth rates in each population and harvest rates depending on the needs of the harvester. To overcome these conditions, there is a concept that accommodates the problem of uncertainty, namely the fuzzy concept. This concept can be induced into a logistic model with proportional harvesting which assumes the intrinsic growth rate and the harvest rate is expressed by fuzzy numbers. The purpose of this research is to form a logistic model with fuzzy proportional harvesting, analyze the stability of the model, and form a numerical simulation. This study uses the alpha-cut method to generalize the intrinsic growth rate and harvest rate from crisp numbers to fuzzy numbers, then the Graded Mean Integration Representation (GMIR) method to defuzzify the model, and the linearization method to analyze the stability of the model. The results of this study obtained a logistic model with proportional harvesting. Then the model was developed into a logistic model with fuzzy proportional harvesting by assuming the intrinsic growth rate and the harvest rate expressed by fuzzy numbers. From the model obtained 2 equilibrium points, namely the first equilibrium point is unstable and the second equilibrium point is asymptotically stable under certain conditions. Model simulation is given to show illustration of stability analysis. From the simulation, it can also be shown that the higher the graded mean value, the lower the population.

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