q.rates {fracprolif} | R Documentation |
Estimate Quiescence-Growth Model Rates
Description
Given an mle estimate of the distribution parameters transform into rates of growth and quiescence. The transformation into a growth rate is the exact method of Powell. The quiescence rate uses Poisson estimation. Standard errors are computed using the numerical delta method.
Usage
q.rates(dist, est)
Arguments
dist |
This distribution to use for estimation, e.g. "emg" or "norm" |
est |
An object of class |
Value
An object of class
q_rate containing (d) the growth rate and (q) the quiescence rate as a numeric vector, as well as additional attributes of stderr, n and df used.
Author(s)
Darren Tyson, Shawn Garbett
References
The method of determining growth rate is taken from POWELL E.0. (1956). Growth Rate and Generation Time of Bacteria, with Special Reference to Continuous Culture. J.Gen.Microbial V15,492-511. This makes a robust estimator in the presence of skewed distributions.
See Also
mle-class
q.mle.norm.estimate
q.mle.emg.estimate
qsurvival.nllik
Examples
data(ca1d.erlotinib)
mitotic.lifespans <-
subset(ca1d.erlotinib, !End.of.Expt &
!Death &
!is.na(Lifespan))$Lifespan
censored.lifespans <-
subset(ca1d.erlotinib, End.of.Expt &
!Death &
!is.na(Lifespan))$Lifespan
r <- q.rates("emg", q.mle.emg.estimate(mitotic.lifespans, censored.lifespans))
summary(r)
r['d'] # Rate of division
r['q'] # Rate of quiescense