Khosravi Abbas, Nahavandi Saeid, Creighton Doug, Atiya Amir F
Centre for Intelligent Systems Research, Deakin University, Geelong, Victoria 3117, Australia.
IEEE Trans Neural Netw. 2011 Sep;22(9):1341-56. doi: 10.1109/TNN.2011.2162110. Epub 2011 Jul 29.
This paper evaluates the four leading techniques proposed in the literature for construction of prediction intervals (PIs) for neural network point forecasts. The delta, Bayesian, bootstrap, and mean-variance estimation (MVE) methods are reviewed and their performance for generating high-quality PIs is compared. PI-based measures are proposed and applied for the objective and quantitative assessment of each method's performance. A selection of 12 synthetic and real-world case studies is used to examine each method's performance for PI construction. The comparison is performed on the basis of the quality of generated PIs, the repeatability of the results, the computational requirements and the PIs variability with regard to the data uncertainty. The obtained results in this paper indicate that: 1) the delta and Bayesian methods are the best in terms of quality and repeatability, and 2) the MVE and bootstrap methods are the best in terms of low computational load and the width variability of PIs. This paper also introduces the concept of combinations of PIs, and proposes a new method for generating combined PIs using the traditional PIs. Genetic algorithm is applied for adjusting the combiner parameters through minimization of a PI-based cost function subject to two sets of restrictions. It is shown that the quality of PIs produced by the combiners is dramatically better than the quality of PIs obtained from each individual method.
本文评估了文献中提出的用于神经网络点预测构建预测区间(PI)的四种主要技术。对德尔塔法、贝叶斯法、自助法和均值 - 方差估计(MVE)方法进行了综述,并比较了它们生成高质量PI的性能。提出了基于PI的度量,并将其应用于对每种方法性能的客观和定量评估。选择了12个合成和实际案例研究来检验每种方法在PI构建方面的性能。基于生成的PI的质量、结果的可重复性、计算要求以及PI相对于数据不确定性的变异性进行比较。本文获得的结果表明:1)德尔塔法和贝叶斯法在质量和可重复性方面最佳;2)MVE法和自助法在低计算量和PI的宽度变异性方面最佳。本文还介绍了PI组合的概念,并提出了一种使用传统PI生成组合PI的新方法。应用遗传算法通过最小化基于PI的成本函数并受制于两组限制来调整组合器参数。结果表明,组合器生成的PI的质量明显优于从每种单独方法获得的PI的质量。