This is a R/Rcpp package BayesSurvive for Bayesian +survival models with graph-structured selection priors for sparse +identification of high-dimensional features predictive of survival (Madjar +et al., 2021) and its extensions with the use of a fixed graph via a +Markov Random Field (MRF) prior for capturing known structure of +high-dimensional features, e.g. disease-specific pathways from the Kyoto +Encyclopedia of Genes and Genomes (KEGG) database.
+Install the latest released version from CRAN
+ +Install the latest development version from GitHub
+ +## Initial value: null model without covariates
+initial = list("gamma.ini" = rep(0, ncol(dataset$X)))
+# Prior parameters
+hyperparPooled = list(
+ "c0" = 2, # prior of baseline hazard
+ "tau" = 0.0375, # sd (spike) for coefficient prior
+ "cb" = 20, # sd (slab) for coefficient prior
+ "pi.ga" = 0.02, # prior variable selection probability for standard Cox models
+ "a" = -4, # hyperparameter in MRF prior
+ "b" = 0.1, # hyperparameter in MRF prior
+ "G" = simData$G # hyperparameter in MRF prior
+)
+
+## run Bayesian Cox with graph-structured priors
+set.seed(123)
+fit <- BayesSurvive(survObj = dataset, model.type = "Pooled", MRF.G = TRUE,
+ hyperpar = hyperparPooled, initial = initial,
+ nIter = 200, burnin = 100)
+
+## show posterior mean of coefficients and 95% credible intervals
+library("GGally")
+plot(fit) +
+ coord_flip() +
+ theme(axis.text.x = element_text(angle = 90, size = 7))
Show the index of selected variables by controlling Bayesian false +discovery rate (FDR) at the level \(\alpha = +0.05\)
+ +#[1] 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 194
+The function BayesSurvive::plotBrier()
can show the
+time-dependent Brier scores based on posterior mean of coefficients or
+Bayesian model averaging.
We can also use the function BayesSurvive::predict()
to
+obtain the Brier score at time 8.5, the integrated Brier score (IBS)
+from time 0 to 8.5 and the index of prediction accuracy (IPA).
## Brier(t=8.5) IBS(t:0~8.5) IPA(t=8.5)
+## Null.model 0.2290318 0.08185316 0.0000000
+## Bayesian.Cox 0.1013692 0.02823275 0.5574011
+The function BayesSurvive::predict()
can estimate the
+survival probabilities and cumulative hazards.
# observation times cumhazard survival
+## <int> <num> <num> <num>
+## 1: 1 3.3 7.41e-05 1.00e+00
+## 2: 2 3.3 2.51e-01 7.78e-01
+## 3: 3 3.3 9.97e-07 1.00e+00
+## 4: 4 3.3 1.84e-03 9.98e-01
+## 5: 5 3.3 3.15e-04 1.00e+00
+## ---
+## 9996: 96 9.5 7.15e+00 7.88e-04
+## 9997: 97 9.5 3.92e+02 7.59e-171
+## 9998: 98 9.5 2.81e+00 6.02e-02
+## 9999: 99 9.5 3.12e+00 4.42e-02
+## 10000: 100 9.5 1.97e+01 2.79e-09
+# specify a fixed joint graph between two subgroups
+hyperparPooled$G <- Matrix::bdiag(simData$G, simData$G)
+dataset2 <- simData[1:2]
+dataset2 <- lapply(dataset2, setNames, c("X", "t", "di", "X.unsc", "trueB"))
+fit3 <- BayesSurvive(survObj = dataset2,
+ hyperpar = hyperparPooled, initial = initial,
+ model.type="CoxBVSSL", MRF.G = TRUE,
+ nIter = 10, burnin = 5)
++Katrin Madjar, Manuela Zucknick, Katja Ickstadt, Jörg Rahnenführer +(2021). Combining heterogeneous subgroups with graph‐structured variable +selection priors for Cox regression. BMC Bioinformatics, +22(1):586. DOI: 10.1186/s12859-021-04483-z.
+