Table 2 Performance metrics of four classifiers (SVM, LDA, LR, and TREE) evaluated through leave-one-out cross-validation on the LGI-PPGI dataset.

From: Optimal signal quality index for remote photoplethysmogram sensing

Excellent vs. Unfit

 

Index

NSQI

ESQI

KSQI

PSQI

ZSQI

RSQI

SSQI

MSQI

Overall

OF1

0.77

0.75

0.75

0.51

0.5

0.49

0.45

0.27

SVM

SE

0.81

0.76

0.81

0.37

0.52

NaN

0.35

NaN

PP

0.82

0.78

0.77

0.55

0.63

NaN

0.56

NaN

F1

0.81

0.76

0.79

0.54

0.7

NaN

0.53

NaN

LDA

SE

0.81

0.81

0.81

0.41

0.4

NaN

0.4

NaN

PP

0.82

0.79

0.73

0.41

0.65

NaN

0.61

NaN

F1

0.81

0.79

0.77

0.62

0.61

NaN

0.61

NaN

LOGI

SE

0.76

0.76

0.74

0.37

0.3

NaN

0.35

NaN

PP

0.81

0.85

0.79

0.56

0.62

NaN

0.61

NaN

F1

0.78

0.8

0.76

0.65

0.51

NaN

0.56

NaN

TREE

SE

0.69

0.64

0.74

0.5

0.45

0.5

0.46

0.29

PP

0.67

0.67

0.61

0.55

0.41

0.49

0.47

0.26

F1

0.68

0.65

0.67

0.51

0.43

0.49

0.47

0.27

Excellent vs. Acceptable

 

Index

NSQI

ESQI

KSQI

SSQI

MSQI

ZSQI

PSQI

RSQI

Overall

OF1

0.72

0.69

0.68

0.67

0.67

0.66

0.64

0.59

SVM

SE

0.92

0.92

0.72

0.82

0.82

0.82

0.63

0.73

PP

0.63

0.63

0.58

0.61

0.61

0.61

0.55

0.58

F1

0.75

0.75

0.63

0.7

0.7

0.7

0.59

0.65

LDA

SE

0.92

0.82

0.82

0.82

0.82

0.82

0.72

0.65

PP

0.63

0.65

0.61

0.61

0.69

0.61

0.58

0.55

F1

0.75

0.72

0.7

0.7

0.75

0.7

0.63

0.59

LOGI

SE

1.00

0.82

0.82

0.82

0.82

0.82

0.82

0.65

PP

0.66

0.65

0.61

0.61

0.69

0.61

0.61

0.55

F1

0.79

0.72

0.7

0.7

0.75

0.7

0.7

0.59

TREE

SE

0.55

0.57

0.73

0.63

0.43

0.55

0.75

0.45

PP

0.6

0.57

0.67

0.55

0.5

0.51

0.57

0.63

F1

0.57

0.57

0.7

0.59

0.48

0.53

0.65

0.52

Acceptable vs. Unfit

 

Index

KSQI

PSQI

NSQI

ZSQI

ESQI

MSQI

SSQI

RSQI

Overall

OF1

0.68

0.67

0.57

0.5

0.4

0.36

NaN

NaN

SVM

SE

0.38

0

0.38

0.38

0

0

0

0

PP

0.75

NaN

0.6

NaN

NaN

NaN

NaN

NaN

F1

0.75

NaN

0.67

NaN

NaN

NaN

NaN

NaN

LDA

SE

0.38

0

0.38

0

0.25

0

0

0

PP

0.38

NaN

0.3

0

0.67

0.0

NaN

NaN

F1

0.75

NaN

0.67

NaN

0.57

NaN

NaN

NaN

LOGI

SE

0.25

0

0.13

0

0.13

0

0

NaN

PP

0.67

NaN

0.17

NaN

0.5

0

NaN

NaN

F1

0.57

NaN

0.29

NaN

0.33

NaN

NaN

NaN

TREE

SE

0.38

0.25

0.38

0.25

0.13

0.25

0

0

PP

0.3

0.5

0.3

0.25

0.17

0.14

0

0

F1

0.67

0.67

0.67

0.5

0.29

0.36

NaN

NaN

  1. Binary classification was executed on rPPG signals derived using CHROM, GREEN, and OMIT methods within three distinct signal quality classes: Excellent, Acceptable, and Unfit. Reported metrics are Sensitivity (SE), Positive Predictivity (PP), and F1 score (F1). The NSQI index was found to be most effective in Excellent vs. Unfit and Excellent vs. Acceptable comparisons, whereas KSQI was predominant in the Acceptable vs. Unfit comparison. Note: OF1 denotes the overall F1 score, the mean of the F1 scores across the four classifiers.
  2. Bolded numbers indicate the highest classification rate achieved.