VGAM (version 0.9-6)

AA.Aa.aa: The AA-Aa-aa Blood Group System

Description

Estimates the parameter of the AA-Aa-aa blood group system, with or without Hardy Weinberg equilibrium.

Usage

AA.Aa.aa(linkp = "logit", linkf = "logit", inbreeding = TRUE,
         ipA = NULL, ifp = NULL, zero = NULL)

Arguments

linkp, linkf

Link functions applied to pA and f. See Links for more choices.

ipA, ifp

Optional initial values for pA and f.

inbreeding

Logical. Is the inbreeding coefficient $f$ equal to 0?

zero

See CommonVGAMffArguments for information.

Value

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

Warning

Setting inbreeding = FALSE makes estimation difficult with non-intercept-only models. Currently, this code seems to work with intercept-only models.

Details

This one or two parameter model involves a probability called pA. The probability of getting a count in the first column of the input (an AA) is pA*pA. When inbreeding = TRUE, an additional parameter f is used. If inbreeding = FALSE then $f = 0$.

References

Weir, B. S. (1996) Genetic Data Analysis II: Methods for Discrete Population Genetic Data, Sunderland, MA: Sinauer Associates, Inc.

See Also

AB.Ab.aB.ab, ABO, A1A2A3, MNSs.

Examples

y <- cbind(53, 95, 38)
fit1 <- vglm(y ~ 1, AA.Aa.aa(linkp = "probit"), trace = TRUE)
fit2 <- vglm(y ~ 1, AA.Aa.aa(inbreeding = FALSE), trace = TRUE)
rbind(y, sum(y) * fitted(fit1))
Coef(fit1)  # Estimated pA
Coef(fit2)  # Estimated pA and f
summary(fit1)