In this article, I discuss the problem of automatic detection of coarse measurements (outliers) in the time series of measurement data generated by technical devices. Solving this problem is of great importance to improve the accuracy of estimates of various physical quantities obtained in solving many applications in which the input data is observations. Since outliers adversely affect the accuracy of final results, they must be detected and removed from further calculations at the stage of data preprocessing and analysis. This can be done in various ways, since the concept of outliers does not have a strict definition in statistics. The author of the article previously formulated the problem of finding the optimal solution that satisfies the condition of maximizing the amount of measuring data that remained after removal of outliers and proposed a robust algorithm for finding such a solution. The complexity of this algorithm is estimated of the order of magnitude $ (N+{N}_{out}^{2}) $, where N is the number of source data and Nout is the number of outliers detected. For highly noisy data, the number of outliers can be extremely large, for example, comparable to N. In this case, it will take about N2 arithmetic operations to find the optimal solution using the algorithm developed earlier. I propose a new algorithm for finding the optimal solution, requiring the order of NlogN arithmetic operations, regardless of the number of outliers detected. The efficiency of the algorithm is manifested when cleaning from outliers large amounts of highly noisy measuring data containing a great many of outliers. The algorithm can be used for automated cleaning from outliers of observation data in information and measuring systems, in systems with artificial intelligence, as well as when solving various scientific, applied managerial and other problems using modern computer systems in order to obtain promptly the most accurate final result.
Citation: Igor V. Bezmenov. Fast algorithm for cleaning highly noisy measurement data from outliers, based on the search for the optimal solution with the minimum number of rejected measurement data[J]. Metascience in Aerospace, 2024, 1(1): 110-129. doi: 10.3934/mina.2024005
In this article, I discuss the problem of automatic detection of coarse measurements (outliers) in the time series of measurement data generated by technical devices. Solving this problem is of great importance to improve the accuracy of estimates of various physical quantities obtained in solving many applications in which the input data is observations. Since outliers adversely affect the accuracy of final results, they must be detected and removed from further calculations at the stage of data preprocessing and analysis. This can be done in various ways, since the concept of outliers does not have a strict definition in statistics. The author of the article previously formulated the problem of finding the optimal solution that satisfies the condition of maximizing the amount of measuring data that remained after removal of outliers and proposed a robust algorithm for finding such a solution. The complexity of this algorithm is estimated of the order of magnitude $ (N+{N}_{out}^{2}) $, where N is the number of source data and Nout is the number of outliers detected. For highly noisy data, the number of outliers can be extremely large, for example, comparable to N. In this case, it will take about N2 arithmetic operations to find the optimal solution using the algorithm developed earlier. I propose a new algorithm for finding the optimal solution, requiring the order of NlogN arithmetic operations, regardless of the number of outliers detected. The efficiency of the algorithm is manifested when cleaning from outliers large amounts of highly noisy measuring data containing a great many of outliers. The algorithm can be used for automated cleaning from outliers of observation data in information and measuring systems, in systems with artificial intelligence, as well as when solving various scientific, applied managerial and other problems using modern computer systems in order to obtain promptly the most accurate final result.
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