Efficient methods for fitting nonlinear non-Gaussian state-space models of wildlife population dynamics

拟合野生动物种群动态非线性非高斯状态空间模型的有效方法

• 批准号: 1946947
• 金额: --
• 依托单位: University of St Andrews
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2017
• 资助国家: 英国
• 起止时间: 2017 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-1946947
• 关键词: Efficient; methods; fitting; nonlinear; non

Recent years have seen an enormous growth in interest in and methods for fitting mechanisticmodels of wildlife population dynamics to survey data on animal numbers, survival and birth rates.Various statistical methods have been proposed, based both on maximum likelihood and Bayesianapproaches. Examples include the Kalman filter (and extensions) for maximum likelihood estimationand Markov chain Monte Carlo (MCMC) or particle filtering for Bayesian models. Each hasadvantages and disadvantages - for example the Kalman filter is designed for linear Gaussian models(but seems to do remarkably well in other circumstances); MCMC is an excellent omnibus methodbut it can be difficult to derive efficient samplers (i.e., those that produce reliable answers in areasonable amount of computer time); particle filtering is easy to program but very inefficient forsome models (e.g., those with random effects). In this project, we aim to blend aspects of theseapproaches to increase the efficiency of the estimation. For example, we will investigate usingKalman filter estimates as importance sampling starts in a particle filter algorithm, and using theparticle filter to provide proposals in an MCMC algorithm.

近年来，人们对用野生动物数量、存活率和出生率的调查数据拟合野生动物种群动态的力学模型的兴趣和方法有了极大的增长，提出了各种基于最大似然法和贝叶斯方法的统计方法。例子包括卡尔曼滤波器（和扩展）的最大似然估计和马尔可夫链蒙特卡罗（MCMC）或粒子滤波贝叶斯模型。每种方法都有优点和缺点-例如卡尔曼滤波器是为线性高斯模型设计的（但在其他情况下似乎做得非常好）; MCMC是一种优秀的综合方法，但很难得到有效的采样器（即，在合理的计算机时间量内产生可靠答案的那些）;粒子滤波易于编程但对于某些模型非常低效（例如，具有随机效应的那些）。在这个项目中，我们的目标是融合这些方法的各个方面，以提高估计的效率。例如，我们将研究在粒子滤波算法中使用卡尔曼滤波估计作为重要性采样的开始，以及使用粒子滤波在MCMC算法中提供建议。