AB.Ab.aB.ab2 {VGAM}R Documentation

The AB-Ab-aB-ab2 Blood Group System

Description

Estimates the parameter of the the AB-Ab-aB-ab2 blood group system.

Usage

AB.Ab.aB.ab2(link = "logit", earg=list(), init.p = NULL)

Arguments

link Link function applied to p. See Links for more choices.
earg List. Extra argument for the link. See earg in Links for general information.
init.p Optional initial value for p.

Details

This one parameter model involves a probability called p.

Value

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

Warning

There may be a bug in the deriv and weight slot of the family function.

Note

The input can be a 4-column matrix of counts. 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.

Author(s)

T. W. Yee

References

Elandt-Johnson, R. C. (1971) Probability Models and Statistical Methods in Genetics, New York: Wiley.

See Also

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

Examples

# See Elandt-Johnson, pp.430,427
# Estimated variance is approx 0.0021
y = cbind(68, 11, 13, 21)
fit = vglm(y ~ 1, AB.Ab.aB.ab2(link=logit), trace=TRUE, crit="coef")
fit = vglm(y ~ 1, AB.Ab.aB.ab2(link=cloglog), trace=TRUE, crit="coef")
Coef(fit)   # Estimated p
rbind(y, sum(y)*fitted(fit))
diag(vcov(fit))^0.5

[Package VGAM version 0.7-7 Index]