pvaft: Estimates of univariate covariates using Accelerated Failure time (AFT) model without MCMC.
Description
Provides list of covariates and their estimates of parametric AFT model with smooth time functions, whose p value is less than chosen value (by default p=1 that is all chosen covariates come in result). Using AFT model for univariate in high dimensional data without MCMC.
Usage
pvaft(m, n, STime, Event, p = 1, data)
Arguments
m
Starting column number of covariates of study in high dimensional entered data.
n
Ending column number of covariates of study in high dimensional entered data.
STime
name of survival time in data.
Event
name of event in data. 0 is for censored and 1 for occurrence of event.
p
p-value, to make restriction for selection of covariates, default value is 1.
data
High dimensional gene expression data that contains event status, survival time and and set of covariates.
Value
Matrix that contains survival information of selected covariates(selected from chosen columns whose p value is <= p) on AFT model. Result shows together for all covariates chosen from column m to n.
Details
Survival time T for covariate x, is modelled as AFT model using
$$S(T|x)=S_0(T\exp(-\eta(x;\beta)))$$
and baseline survival function is modelled as
$$S_0(T)=\exp(-\exp(\eta_0(log(T);\beta_0)))$$
Where \(\eta\) and \(\eta\) are linear predictor.