Table 1:

R functions for fitting shared frailty models. NP = nonparametric, P = parametric, PPL = penalized partial likelihood, NLS = nonlinear least squares, EM = expectation maximization, PFL = pseudo full likelihood, HL = h-likelihood, MML = maximum marginal likelihood, LN = log-normal, LT = log-t, IG = inverse Gaussian, PS = positive stable. Weekly downloads are averages from the time the package first appears on the RStudio CRAN mirror through 2016-06-01, as reported by the RStudio CRAN package download logs: http://cran-logs.rstudio.com/.

package: :function	λ0	Estimation procedure	Frailty distributions	Weekly downloads
survival: :coxph	NP	PPL	Gamma, LN, LT	3905
gss: : sscox	NP	PPL	LN	1120
coxme: :coxme	NP	PPL	LN	260
frailtypack: :frailtyPenal	NP	NLS	Gamma, LN	98
R2BayesX: :bayesx	NP	PPL	LN	58
phmm: :phmm	NP	EM	LN	52
frailtySurv: :fitfrail	NP	PFL	Gamma, LN, IG, PVF	50
frailtyHL: :frailtyHL	NP	HL	Gamma, LN	50
parfm: :parfm	P	MML	Gamma, PS, IG	49
survBayes: :survBayes	NP	Bayes	Gamma, LN	28