Research Article

Modified Robust Ridge M-Estimators in Two-Parameter Ridge Regression Model

Table 4

Estimated MSE for n = 20, , and 20% outlier in the y-direction.

Correlation (δ2)Error variance (σ2)OLSMREMREM1TRME1MTPM1MTPM2MTPM3TRME2MTPM4MTPM5MTPM6

0.850.111.81240.07035.1810.02710.02580.01830.01090.01270.02930.01020.01100.01160.0129
111.83120.21315.19560.06840.06480.04950.02030.03590.08060.02470.02160.02710.0368
512.33814.43215.57221.68311.60241.38150.94101.51661.80050.93681.05171.28581.4946
1014.171111.31156.854.69424.32093.42072.63804.16825.23272.41872.85763.41283.9952

0.950.131.4220.150612.86670.04880.04590.03300.00950.02540.05920.01270.00990.01410.0247
131.51190.566112.92020.19190.18130.15250.05360.15450.20460.07280.05930.10210.1516
533.040612.45214.1394.95874.66764.0542.41464.9794.64192.55012.90274.18044.6898
1039.296132.800918.359613.687812.53479.85956.708414.198114.22176.77057.830911.196613.0773

0.990.1140.33180.758755.44640.39010.36930.35910.21650.39660.27900.26140.22230.32100.3728
1140.6192.797655.58951.29681.22611.16330.63981.27100.91870.77270.67501.09891.2139
5149.594361.19863.620526.392724.739921.907712.54724.294719.80713.850614.86224.717323.900
10178.399158.420681.718369.209463.452851.755832.14370.228962.610234.601437.846464.508267.7464

0.9990.11315.5256.6983512.41023.02992.8312.67471.28642.54621.89251.64941.30832.61092.8092
11318.78326.1026518.487111.470410.719810.20124.66388.92977.15426.0094.831510.636310.1794
51387.456565.0867597.5064243.5939226.9272205.540496.7687181.1837165.0595119.0271109.1384236.7054197.67
101720.9311556.154800.0413678.0977620.283492.9333269.8147619.7776591.5999319.3605307.8377675.9897642.3477