Discretized butterfly optimization algorithm for variable selection in rapid determination of cholesterol by near infrared spectroscopy
writer：Xihui Bian*, Zizhen Zhao, Jianwen Liu, Peng Liu, Huibing Shi, Xiaoyao Tan
keywords：Swarm intelligence optimization algorithm; Variable selection; Multivariate calibration; Blood analysis
source：期刊
specific source：Analytical Methods, 2023, 15, 5190-5198
Issue time：2023年
The blood cholesterol level is strongly associated with cardiovascular disease. It is necessary to develop a rapid method for determination cholesterol concentration of blood. In this study, discretized butterfly optimization algorithm - partial least squares (BOA-PLS) combined with near infrared (NIR) is firstly proposed for rapid determination cholesterol concentration in blood. In discretized BOA, the butterfly vector is described by 1 or 0, which represents the variable is selected or not. In the optimization process, four transfer functions, i.e., arctangent, V-shaped, improved arctangent (I-atan) and improved V-shaped (I-V) functions are introduced and compared for discretization the position of butterflies. Partial least squares (PLS) model is established between the selected NIR variables and cholesterol concentrations. The iteration number, transfer functions and the performance of butterflies are investigated. The proposed method is compared with full-spectrum PLS, multiplicative scatter correction-PLS (MSC-PLS), Max-min scaling-PLS (MMS-PLS), MSC-MMS-PLS, uninformative variable elimination-PLS (UVE-PLS), Monte Carlo uninformative variable elimination-PLS (MCUVE-PLS) and randomization test-PLS (RT-PLS). Results show that I-V function is the best transfer function for discretization. Both preprocessing and variable selection can improve the prediction performance of PLS. Variable selection methods based on BOA are better than those based on statistics. Furthermore, I-V-BOA-PLS has the highest predictive accuracy among the seven variable selection methods. In addition, MSC-MMS can further improve the prediction ability of I-V-BOA-PLS. Therefore, BOA-PLS combined with NIR spectroscopy are promising for rapid determination of cholesterol concentration in blood.