Research Article

Determinant Efficiencies in Ill-Conditioned Models

Table 1

Roots 𝐺 ( 𝜷 ) and 𝜷 𝐺 ( 𝑖 ) of generalized variances for 𝜷 and subset estimators { 𝜷 𝑖 𝑡 } , and angles 𝜙 ( 1 𝑛 𝐗 ) 𝑑 𝑒 𝑔 between regressors and the constant, against reference values 𝜙 < 1 8 . 4 4 and 𝜙 < 3 0 . 0 0 , in eight small second-order designs.

Design 𝐺 ( 𝜷 ) ̂ 𝛽 𝐺 ( 0 ) 𝜷 𝐺 ( 𝐿 ) 𝜷 𝐺 ( 𝑄 ) 𝜷 𝐺 ( 𝐼 ) 𝜷 𝐺 ( 𝑄 , 𝜷 𝐼 ) 𝜷 𝐺 ( 𝑀 ) 𝜙 ( 𝟏 𝑛 𝐗 )

H 3 1 0 1.49916 5.0477 1.18821 2.08026 1.61045 1.83034 1.58484 25.11*
H 3 1 1 B 1.28050 10.0000 1.0000 1.17680 1.99997 1.53413 1.33017 17.55**
S C D 1.53876 10.0000 1.66667 1.04210 4.16667 2.08376 1.63142 17.55**
B B D 1.10533 10.0000 0.83333 1.64583 1.11111 1.35229 1.15077 16.10**
C C D 0.93725 10.0000 0.71429 1.03300 1.25000 1.13633 0.97341 14.96**
N D 2.03063 8.7500 1.25000 7.80031 1.25000 3.12256 2.22030 18.80*
H D 2.33258 5.0000 1.91189 6.61313 1.95275 3.57444 2.59004 25.24*
B D D 2.21835 4.6477 1.58809 4.96625 2.25752 3.22673 2.44950 26.25*