VGAM (version 0.8-1)

ABO: The ABO Blood Group System

Description

Estimates the two independent parameters of the the ABO blood group system.

Usage

ABO(link = "logit", earg=list(), ipA = NULL, ipO = NULL)

Arguments

link

Link function applied to pA and pB. See Links for more choices.

earg

List. Extra argument applied to each of the links. See earg in Links for general information.

ipA, ipO

Optional initial value for pA and pO. A NULL value means values are computed internally.

Value

• An object of class "vglmff" (see vglmff-class). The object is used by modelling functions such as vglm and vgam.

Details

The parameters pA and pB are probabilities, so that pO=1-pA-pB is the third probability. The probabilities pA and pB correspond to A and B respectively, so that pO is the probability for O. It is easier to make use of initial values for pO than for pB. In documentation elsewhere I sometimes use pA=p, pB=q, pO=r.

References

Lange, K. (2002) Mathematical and Statistical Methods for Genetic Analysis, 2nd ed. New York: Springer-Verlag.

See Also

AA.Aa.aa, AB.Ab.aB.ab, AB.Ab.aB.ab2, G1G2G3, MNSs.

Examples

y = cbind(A=725, B=258, AB=72, O=1073) # Order matters, not the name
fit = vglm(y ~ 1, ABO(link=identity), trace=TRUE, cri="coef")
coef(fit, matrix=TRUE)
Coef(fit) # Estimated pA and pB
rbind(y, sum(y)*fitted(fit))
sqrt(diag(vcov(fit)))