Research Article

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

Table 1

Estimated MSE for n = 20, , and 10% outlier in the y-direction.

Correlation (δ2)Error variance (σ2)OLSMREMREM1TRME1MTPM1MTPM2MTPM3TRME2MTPM4MTPM5MTPM6

0.850.129.92740.050223.24040.02610.02160.01060.00830.00850.02310.00890.00840.00840.0086
129.94450.141723.24200.06320.04950.02880.00930.01310.07740.01270.00940.01030.0127
530.42983.391523.19251.78381.50591.46810.68181.42202.26340.78860.73810.95421.3006
1032.443413.117223.63507.11916.09156.20933.30077.06528.81033.39573.64934.86886.4071

0.950.197.11150.118174.86290.05170.04010.02040.00640.00990.07520.00870.00640.00690.0091
197.23800.437574.92890.19900.15780.12510.03130.09150.28650.04990.03230.04280.0737
598.376010.795874.26755.61844.71914.80341.81246.14137.17792.33442.03833.37995.1130
10105.498942.304576.329722.412318.971119.93218.079827.059828.22469.45869.709317.066623.7698

0.990.1494.53380.6391378.72780.40600.36270.42090.18430.44050.43670.23260.18670.24530.3455
1494.91222.3451378.73371.36561.19141.35490.51901.57441.56930.68760.53160.80231.2228
5503.299357.3636378.200130.961926.346428.680710.208138.839437.962013.735511.173323.561434.3006
10532.7590213.6679381.2322114.274597.1373105.523237.3810143.7064141.020348.293843.5950101.2758134.1682

0.9990.14969.13445.74043794.81733.19262.75303.11481.05613.93113.77961.47351.06161.67933.0110
14973.982122.56883796.939712.142210.366511.44083.768915.151914.79095.38053.80517.142212.6832
54995.4508540.77463730.1907281.9896239.2546258.569183.8542353.4930350.4758118.926687.5022245.6556339.7473
105377.67502152.12313860.40201142.1380967.54221063.4883321.19691428.46561422.1817453.0490348.15261126.79811402.4136