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Updated: Jun 14, 2025

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使用Wishart过程和顺序的蒙特卡洛过程,对动态共变率进行了强大的推断
Hester Huijsdens1, David Leeftink1, Linda Geerligs1
1Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Thomas van Aquinostraat 4, 6525 GD Nijmegen, The Netherlands.
Entropy (Basel, Switzerland)
|August 29, 2024
概括
我们为Wishart过程开发了一种序列蒙特卡洛 (SMC) 采样器,改进了动态协差估计. 这种贝叶斯非参数方法提供了可靠的预测,超过了MCMC和变量推理,特别是在复杂的协差函数中.
科学领域:
- 统计 统计 统计 统计
- 计算神经科学是一种神经科学.
- 计量经济学 计量经济学
背景情况:
- 随着时间的推移,动态相互作用在计量经济学,神经科学和计算心理学中被研究.
- 维沙特过程是一个贝叶斯的非参数模型,有效用于时间序列分析,但推断是具有挑战性的.
- 现有的推理方法,如MCMC和变量推理有局限性.
研究的目的:
- 介绍一个新的顺序蒙特卡洛 (SMC) 采样器,用于Wishart过程.
- 将SMC采样器的性能与传统的MCMC和变异推理方法进行比较.
- 证明拟议的方法用于分析动态协差结构的实用性.
主要方法:
- 开发了一个为Wishart过程量身定制的序列蒙特卡洛 (SMC) 采样器.
- 进行模拟研究以评估估计和预测准确性.
- 将SMC采样器应用于临床抑郁症数据集.
主要成果:
- SMC采样提供了最可靠的动态共变率估计和样本外预测.
- SMC的表现优于MCMC和变异推理,特别是在复合共变函数和相关参数方面.
- 该方法准确地代表了后部分布,使得协差动态的有效测试成为可能.
结论:
- 与现有的方法相比,拟议的SMC采样器为Wishart过程提供了更强大,更准确的推断方法.
- 这一进步有助于在各种科学领域更好地建模动态共变量.
- 这种方法实际上适用于分析复杂的时间序列数据和测试动态变化.
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