B_all

Local beta coefficients from source sites 
B_source

Local beta coefficients from source sites 
Sigma_all

Data covariance matrix from each site. 
Sigma_target

Data covariance matrix from the target site. 
delta.valid

Status indicator for the validation dataset. 
survmaximin()

Generate transferlearning survmaximin coefficients 
survmaximin_fed()

Generate federatelearning coefficients 
x.valid

Time to event for the validation dataset. 
z.valid

Baseline covariates in the validation dataset. 