ABO {VGAM} | R Documentation |
Estimates the two independent parameters of the the ABO blood group system.
ABO(link = "logit", earg=list(), ir = NULL, ip = NULL)
link |
Link function applied to p and q .
See Links for more choices.
|
earg |
List. Extra argument applied to each of the links.
See earg in Links for general information.
|
ir, ip |
Optional initial value for r and p .
A NULL value means values are computed internally. |
The parameters p
and q
are probabilities, so that
r=1-p-q
is the third probability.
The probabilities p
and r
correspond to
A and O respectively, so that q
is the probability for B.
It is easier to make use of initial values for r
than for
q
.
An object of class "vglmff"
(see vglmff-class
).
The object is used by modelling functions such as vglm
and vgam
.
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.
T. W. Yee
Lange, K. (2002) Mathematical and Statistical Methods for Genetic Analysis, 2nd ed. New York: Springer-Verlag.
AA.Aa.aa
,
AB.Ab.aB.ab
,
AB.Ab.aB.ab2
,
G1G2G3
,
MNSs
.
y = cbind(A=725, B=258, AB=72, O=1073) # Order matters, not the name fit = vglm(y ~ 1, ABO(link=logit), trace=TRUE, cri="coef") fit = vglm(y ~ 1, ABO(link=identity), trace=TRUE, cri="coef") coef(fit, matrix=TRUE) Coef(fit) # Estimated p and q rbind(y, sum(y)*fitted(fit)) sqrt(diag(vcov(fit)))