Implementations in R of classical general-purpose algorithms generally have two major limitations which make them unusable in complex problems: too loose convergence criteria and too long calculation time. By relying on a Marquardt-Levenberg algorithm (MLA), a Newton-like method particularly robust for solving local optimization problems, we provide with marqLevAlg package an efficient and general-purpose local optimizer which (i) prevents convergence to saddle points by using a stringent convergence criterion based on the relative distance to minimum/maximum in addition to the stability of the parameters and of the objective function; and (ii) reduces the computation time in complex settings by allowing parallel calculations at each iteration. We demonstrate through a variety of cases from the literature that our implementation reliably and consistently reaches the optimum (even when other optimizers fail), and also largely reduces computational time in complex settings through the example of maximum likelihood estimation of different sophisticated statistical models.
翻译:传统的通用算法在R中的实施通常有两个主要限制,使它们在复杂的问题中无法使用:过于松散的趋同标准和过长的计算时间。我们依靠Marquirdt-Leverberg算法(MLA),这是解决本地优化问题特别有力的一种类似于牛顿的方法,我们向MarqLevAlg提供了高效和通用的地方优化软件包,它(一)通过使用严格的趋同标准,在参数和目标功能的稳定性之外,以最低/最大距离为基础,防止与搭配点的趋同;以及(二)通过允许每次迭代的平行计算来缩短复杂环境下的计算时间。我们通过文献中的各种案例表明,我们的实施可靠和始终如一地达到最佳水平(即使其他优化者未能成功),并且通过对不同的复杂统计模型进行最大可能性的估计,在很大程度上减少了复杂环境中的计算时间。