ABO function

The ABO Blood Group System

The ABO Blood Group System

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

ABO(link.pA = "logitlink", link.pB = "logitlink", ipA = NULL, ipB = NULL, ipO = NULL, zero = NULL)

Arguments

  • link.pA, link.pB: Link functions applied to pA and pB. See Links for more choices.
  • ipA, ipB, ipO: Optional initial value for pA and pB and pO. A NULL value means values are computed internally.
  • zero: Details at CommonVGAMffArguments.

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.

Returns

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

and vgam.

References

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

Author(s)

T. W. Yee

Note

The input can be a 4-column matrix of counts, where the columns are A, B, AB, O (in order). Alternatively, the input can be a 4-column matrix of proportions (so each row adds to 1) and the weights

argument is used to specify the total number of counts for each row.

See Also

AA.Aa.aa, AB.Ab.aB.ab, A1A2A3, MNSs.

Examples

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