midq2q.Rd
This function recovers ordinary conditional quantile functions based on fitted mid-quantile regression models.
midq2q(object, newdata, observed = FALSE, ...)
an object of class
midrq
.
a required data frame in which to look for variables with which to predict.
logical flag. If TRUE
, ordinary quantiles are recovered from observed sample values. Otherwise, they are calcuated as rounded mid-quantiles. See details.
not used.
If the values of the support of the random variable are equally spaced integers, then observed
should ideally be set to FALSE
so that the ordinary quantile is obtained by rounding the predicted mid-quantile. Otherwise, the function returns an integer observed in the sample. See Geraci and Farcomeni for more details.
a vector or a matrix of estimated ordinary quantiles. The attribute Fhat
provides the corresponding estimated cumulative distribution.
Geraci, M. and A. Farcomeni. Mid-quantile regression for discrete responses. arXiv:1907.01945 [stat.ME]. URL: https://arxiv.org/abs/1907.01945.
if (FALSE) { # \dontrun{
# Esterase data
data(esterase)
# Fit quantiles 0.1, 0.15, ..., 0.85
fit <- midrq(Count ~ Esterase, tau = 2:17/20, data = esterase, type = 3, lambda = 0)
# Recover ordinary quantile function
xx <- seq(min(esterase$Esterase), max(esterase$Esterase), length = 5)
print(Qhat <- midq2q(fit, newdata = data.frame(Esterase = xx)))
# Plot
plot(Qhat, sub = TRUE)
} # }