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. Author manuscript; available in PMC: 2022 May 9.
Published in final edited form as: Stat Med. 2021 Jun 23;40(24):5152–5173. doi: 10.1002/sim.9117

TABLE 2.

Performance of principal component analysis (PCA) of hybrid functional and vector data (HFV-PCA) and Ramsay and Silverman’s method (RS-PCA) in terms of RSE(λ^m), RSE(ξ^m) and ASE(ρ^m), m = 1,2,3, averaged across 500 simulated datasets of size n = 200 (with standard deviations in parentheses) for each setting (I/II) and functional data type (SIR/DIR/DR). “Ratio” denotes the RSE and ASE ratios of HFV-PCA to RS-PCA

Setting I
Setting II
Type R(A)SE HFV-PCA RS-PCA Ratio HFV-PCA RS-PCA Ratio
SIR RSE(λ^1) 0.025 (0.026) 0.134 (0.245) 0.189 0.019 (0.022) 1.207 (6.743) 0.016
RSE(λ^2) 0.050 (0.041) 0.493 (0.527) 0.102 0.048 (0.045) 1.168 (1.183) 0.041
RSE(λ^3) 0.192 (0.057) 1.152 (0.939) 0.167 0.138 (0.066) 3.642 (1.964) 0.038
RSE(ξ^1) 0.024 (0.020) 0.148 (0.213) 0.161 0.021 (0.018) 0.584 (0.381) 0.036
RSE(ξ^2) 0.045 (0.027) 0.339 (0.307) 0.132 0.052 (0.036) 0.761 (0.501) 0.068
RSE(ξ^3) 0.255 (0.068) 1.579 (0.418) 0.162 0.165 (0.094) 1.783 (0.181) 0.092
ASE(ρ^1) 0.047 (0.012) 0.427 (0.333) 0.111 0.059 (0.012) 1.193 (1.008) 0.049
ASE(ρ^2) 0.043 (0.015) 0.484 (0.278) 0.088 0.052 (0.016) 0.856 (0.415) 0.060
ASE(ρ^3) 0.026 (0.007) 0.634 (0.172) 0.041 0.030 (0.010) 0.886 (0.148) 0.034

DIR RSE(λ^1) 0.010 (0.013) 0.011 (0.016) 0.903 0.015 (0.011) 0.011 (0.014) 1.336
RSE(λ^2) 0.012 (0.015) 0.013 (0.018) 0.931 0.016 (0.017) 0.017 (0.023) 0.946
RSE(λ^3) 0.009 (0.014) 0.013 (0.022) 0.700 0.011 (0.021) 0.021 (0.028) 0.499
RSE(ξ^1) 0.015 (0.013) 0.017 (0.016) 0.889 0.091 (0.027) 0.091 (0.027) 0.396
RSE(ξ^2) 0.047 (0.028) 0.031 (0.025) 1.514 0.037 (0.041) 0.037 (0.041) 1.292
RSE(ξ^3) 0.060 (0.030) 0.040 (0.027) 1.500 0.265 (0.151) 0.265 (0.151) 0.265
ASE(ρ^1) 0.024 (0.009) 0.030 (0.012) 0.796 0.033 (0.011) 0.051 (0.033) 0.655
ASE(ρ^2) 0.032 (0.014) 0.035 (0.017) 0.918 0.037 (0.015) 0.053 (0.026) 0.703
ASE(ρ^3) 0.028 (0.011) 0.029 (0.010) 0.938 0.036 (0.014) 0.047 (0.047) 0.772

DR RSE(λ^1) 0.010 (0.014) 0.010 (0.014) 0.999 0.010 (0.015) 0.012 (0.014) 0.867
RSE(λ^2) 0.010 (0.014) 0.010 (0.014) 1.012 0.011 (0.014) 0.010 (0.014) 1.015
RSE(λ^3) 0.010 (0.015) 0.010 (0.015) 1.004 0.010 (0.014) 0.028 (0.024) 0.352
RSE(ξ^1) 0.014 (0.014) 0.015 (0.015) 0.950 0.020 (0.014) 0.078 (0.018) 0.251
RSE(ξ^2) 0.029 (0.025) 0.027 (0.024) 1.098 0.034 (0.023) 0.025 (0.021) 1.343
RSE(ξ^3) 0.030 (0.025) 0.031 (0.026) 0.983 0.041 (0.025) 0.192 (0.033) 0.212
ASE(ρ^1) 0.013 (0.009) 0.014 (0.010) 0.972 0.014 (0.009) 0.021 (0.012) 0.664
ASE(ρ^2) 0.019 (0.015) 0.019 (0.015) 0.999 0.019 (0.014) 0.019 (0.016) 0.995
ASE(ρ^3) 0.014 (0.010) 0.014 (0.010) 0.999 0.014 (0.009) 0.019 (0.008) 0.747

Abbreviations: ASE, average squared error; DR, dense and regular; DIR, dense and irregular; RSE, relative squared error; SIR, sparse and irregular.