Aston Robotics, Vision, and Intelligent Systems Lab (ARVIS), School of Engineering and Applied Science, Aston University, Birmingham, United Kingdom.
Department of Electrical and Computer Engineering, Institute of Systems and Robotics, University of Coimbra, Coimbra, Portugal.
PLoS One. 2020 Oct 28;15(10):e0241332. doi: 10.1371/journal.pone.0241332. eCollection 2020.
In this work we present a three-stage Machine Learning strategy to country-level risk classification based on countries that are reporting COVID-19 information. A K% binning discretisation (K = 25) is used to create four risk groups of countries based on the risk of transmission (coronavirus cases per million population), risk of mortality (coronavirus deaths per million population), and risk of inability to test (coronavirus tests per million population). The four risk groups produced by K% binning are labelled as 'low', 'medium-low', 'medium-high', and 'high'. Coronavirus-related data are then removed and the attributes for prediction of the three types of risk are given as the geopolitical and demographic data describing each country. Thus, the calculation of class label is based on coronavirus data but the input attributes are country-level information regardless of coronavirus data. The three four-class classification problems are then explored and benchmarked through leave-one-country-out cross validation to find the strongest model, producing a Stack of Gradient Boosting and Decision Tree algorithms for risk of transmission, a Stack of Support Vector Machine and Extra Trees for risk of mortality, and a Gradient Boosting algorithm for the risk of inability to test. It is noted that high risk for inability to test is often coupled with low risks for transmission and mortality, therefore the risk of inability to test should be interpreted first, before consideration is given to the predicted transmission and mortality risks. Finally, the approach is applied to more recent risk levels to data from September 2020 and weaker results are noted due to the growth of international collaboration detracting useful knowledge from country-level attributes which suggests that similar machine learning approaches are more useful prior to situations later unfolding.
在这项工作中,我们提出了一个三阶段机器学习策略,基于报告 COVID-19 信息的国家对国家进行风险分类。使用 K%分箱离散化(K=25),根据传播风险(每百万人口的冠状病毒病例数)、死亡率风险(每百万人口的冠状病毒死亡数)和检测能力不足风险(每百万人口的冠状病毒检测数),将国家分为四个风险组。K%分箱产生的四个风险组分别标记为“低”、“中低”、“中高”和“高”。然后去除冠状病毒相关数据,将预测三种风险的属性作为描述每个国家的地缘政治和人口统计数据。因此,类别标签的计算基于冠状病毒数据,但输入属性是国家层面的信息,与冠状病毒数据无关。然后通过留一国家外交叉验证探索和基准测试这三个四分类问题,以找到最强模型,为传播风险生成梯度提升和决策树算法堆栈,为死亡率风险生成支持向量机和 Extra Trees 堆栈,为检测能力不足风险生成梯度提升算法。值得注意的是,检测能力不足的高风险通常伴随着传播和死亡率的低风险,因此应首先考虑检测能力不足的风险,然后再考虑预测的传播和死亡率风险。最后,该方法应用于 2020 年 9 月的数据,由于国际合作的增加从国家层面的属性中获取有用知识,风险水平有所下降,这表明在类似的机器学习方法在情况进一步发展之前更有用。