Spanning Sets for Estimable Contrasts in Classification Models
Birkes, David ; Dodge, Yadolah ; Seely, Justus
Ann. Statist., Tome 4 (1976) no. 1, p. 86-107 / Harvested from Project Euclid
Two algorithms, the $R$-process and the $Q$-process, are presented which can be effective tools for determining the estimable contrasts in a classification model. Both algorithms operate on the incidence matrix of the model as opposed to the design matrix. If the model is partitioned as $E(Y_u) = h_u\cdot \xi + t_u \cdot \theta, u \in U$, the $R$-process produces a spanning set for the estimable $\theta$-contrasts (i.e., contrasts involving only $\theta$ parameters) whenever the set of distinct $h_u$ vectors is linearly independent. If the distinct $h_u$ vectors are dependent, the $R$-process is still useful and often simplifies the problem of obtaining a spanning set for the estimable $\theta$-contrasts. After the $R$-process has been applied in a case when the distinct $h_u$ vectors are dependent, the $Q$-process produces a spanning set for the estimable $\theta$-contrasts provided a partition $h_u\cdot \xi = f_u\cdot \phi + g_u\cdot\omega, u \in U$, can be made such that the sets of distinct $f_u$ vectors and distinct $g_u$ vectors are both linearly independent. As examples, the $R$-process is used to investigate the additive two-way model; and the $R$-process and $Q$-process together are used to investigate an additive three-way model, a two-way model with interaction, and a Graeco-Latin square model.
Publié le : 1976-01-14
Classification:  Classification models,  missing observations,  estimable contrasts,  degrees of freedom,  maximal rank design matrices,  62J99,  62K99
@article{1176343349,
     author = {Birkes, David and Dodge, Yadolah and Seely, Justus},
     title = {Spanning Sets for Estimable Contrasts in Classification Models},
     journal = {Ann. Statist.},
     volume = {4},
     number = {1},
     year = {1976},
     pages = { 86-107},
     language = {en},
     url = {http://dml.mathdoc.fr/item/1176343349}
}
Birkes, David; Dodge, Yadolah; Seely, Justus. Spanning Sets for Estimable Contrasts in Classification Models. Ann. Statist., Tome 4 (1976) no. 1, pp.  86-107. http://gdmltest.u-ga.fr/item/1176343349/