Title: | Statistical Learning Methods for Optimizing Dynamic Treatment Regimes |
---|---|
Description: | We provide a comprehensive software to estimate general K-stage DTRs from SMARTs with Q-learning and a variety of outcome-weighted learning methods. Penalizations are allowed for variable selection and model regularization. With the outcome-weighted learning scheme, different loss functions - SVM hinge loss, SVM ramp loss, binomial deviance loss, and L2 loss - are adopted to solve the weighted classification problem at each stage; augmentation in the outcomes is allowed to improve efficiency. The estimated DTR can be easily applied to a new sample for individualized treatment recommendations or DTR evaluation. |
Authors: | Yuan Chen, Ying Liu, Donglin Zeng, Yuanjia Wang |
Maintainer: | Yuan Chen <[email protected]> |
License: | GPL-2 |
Version: | 2.0 |
Built: | 2024-11-15 04:51:36 UTC |
Source: | https://github.com/ychen178/dtrlearn2 |
We provide a two-stage sequential multiple assignment randomized trial (SMART) data of 150 children with ADHD mimicking a real world study. At the first stage, children were randomized to treatment of low-intensity behavioral modification (BMOD) or low-intensity methamphetamine (MED) with equal probability. At second stage, children were randomized to treatment of low-intensity BMOD + low-intensity MED, or high-intensity BMOD with equal probability. The primary outcome of study was children's school performance score ranging from 1 to 5 assessed at the end of the study for all participants.
data("adhd")
data("adhd")
A data frame with 150 observations on the following 11 variables.
id
IDs of the 150 children
o11
baseline covariate coded as 0/1: diagnosed with ODD (oppositional defiant disorder) before the first-stage intervention
o12
baseline covariate: ADHD score at the end of the previous school year (ranging from 0 to 3, larger values for fewer ADHD symptoms)
o13
baseline covariate coded as 0/1: receiving medication during the previous school year
o14
baseline covariate coded as 0/1: race - white (coded 1) versus nonwhite (coded 0)
a1
first-stage intervention coded as -1/1: -1 for low-intensity methamphetamine (MEDS), 1 for low-intensity behavioral modification (BMOD)
r
first-stage response indicator coded as 0/1
o21
intermediate outcome: number of months until non-response (maximum: 8 months, NA for responders)
o22
intermediate outcome coded as 0/1: adherence to the first-stage intervention, 1 for high adherence
a2
second-stage intervention coded as -1/1: -1 for low-intensity BMOD + MEDS, 1 for high-intensity BMOD
y
primary outcome (continuous): school performance at the end of the school year (ranging from 1 to 5, higher values reflect better performance)
Pelham Jr, W. E., & Fabiano, G. A. (2008). Evidence-based psychosocial treatments for attention-deficit/hyperactivity disorder. Journal of Clinical Child & Adolescent Psychology, 37(1), 184-214.
data(adhd) attach(adhd) n = length(a1) H1 = scale(cbind(o11, o12, o13, o14)) H2 = scale(cbind(H1, a1, H1*a1, r, o22, r*a1, o22*a1)) colnames(H2)[12] = "r*a1" colnames(H2)[13] = "o22*a1" fit_ql = ql(H=list(H1, H2), AA=list(a1,a2), RR=list(rep(0, n), y), pi=list(rep(0.5, n), rep(0.5,n)), K=2, m=3, lasso=TRUE) c = 2^c(-3:3) fit_owl = owl(H=list(H1, H2), AA=list(a1,a2), RR=list(rep(0, n), y), n=n, K=2, pi=list(rep(0.5, n), rep(0.5,n)), res.lasso = TRUE, loss="hinge", kernel="linear", augment=TRUE, c=c, m=3)
data(adhd) attach(adhd) n = length(a1) H1 = scale(cbind(o11, o12, o13, o14)) H2 = scale(cbind(H1, a1, H1*a1, r, o22, r*a1, o22*a1)) colnames(H2)[12] = "r*a1" colnames(H2)[13] = "o22*a1" fit_ql = ql(H=list(H1, H2), AA=list(a1,a2), RR=list(rep(0, n), y), pi=list(rep(0.5, n), rep(0.5,n)), K=2, m=3, lasso=TRUE) c = 2^c(-3:3) fit_owl = owl(H=list(H1, H2), AA=list(a1,a2), RR=list(rep(0, n), y), n=n, K=2, pi=list(rep(0.5, n), rep(0.5,n)), res.lasso = TRUE, loss="hinge", kernel="linear", augment=TRUE, c=c, m=3)
This function implements a variety of outcome-weighted learning methods for estimating general K-stage DTRs. Different loss functions - SVM hinge loss, SVM ramp loss, binomial deviance loss, and L2 loss - can be adopted to solve the weighted classification problem at each stage. Augmentation in the outcomes is allowed to improve efficiency especially when there are multiple stages with a small sample size. Cross validation is conducted to choose the best tuning parameters if any.
owl(H, AA, RR, n, K, pi='estimated', res.lasso=TRUE, loss='hinge', kernel='linear', augment=FALSE, c=2^(-2:2), sigma=c(0.03,0.05,0.07), s=2.^(-2:2), m=4, solver='svm')
owl(H, AA, RR, n, K, pi='estimated', res.lasso=TRUE, loss='hinge', kernel='linear', augment=FALSE, c=2^(-2:2), sigma=c(0.03,0.05,0.07), s=2.^(-2:2), m=4, solver='svm')
H |
subject history information before treatment for the |
AA |
observed treatment assignments for all subjects at the |
RR |
observed reward outcomes for all subjects at the |
n |
sample size, number of subjects in the dataset |
K |
number of stages |
pi |
treatment assignment probabilities of the observed treatments for all subjects at the K stages. It is a vector if |
res.lasso |
whether or not to use lasso penalty in the regression to take residuals for constructing the weights. The default is |
loss |
loss function for sovling the weighted classification problem at each stage. The options are |
kernel |
kernel function to use under SVM hinge loss or SVM ramp loss. |
augment |
whether or not to use augmented outcomes at each stage. Augmentation is recommended when there are multiple stages and the sample size is small. The default is |
c |
a vector specifies the values of the regularization parameter C for tuning under SVM hinge loss or SVM ramp loss. The default is |
sigma |
a vector specifies the values of the positive parameter |
s |
a vector specifies the values of the slope parameter in the SVM ramp loss for tuning, i.e., when |
m |
number of folds in the m-fold cross validation for choosing the tuning parameters |
solver |
|
A patient's history information prior to the treatment at stage k can be constructed recursively as with
, where
is subject-specific variables collected at stage k just prior to the treatment,
is the treatment at stage
, and
is the outcome observed post the treatment at stage
. Higher order or interaction terms can also be easily incorporated in
, e.g.,
.
A list of results is returned as an object. It contains the following attributes:
stage1 |
a list of stage 1 results, ... |
stageK |
a list of stage K results |
valuefun |
overall empirical value function under the estimated DTR |
benefit |
overall empirical benefit function under the estimated DTR |
pi |
treatment assignment probabilities of the observed treatments for each subject at the K stages. It is a list of K vectors. If |
type |
object type corresponding to the specified |
In each stage's result, a list is returned which consists of
beta0 |
estimated coefficient of the intercept in the decision function |
beta |
estimated coefficients of |
fit |
fitted decision function for each subject |
probability |
estimated probability that treatment 1 (vs. -1) is the optimal treatment for each subject in the sample. It's calculated by exp(fit)/(1 + exp(fit)). |
treatment |
the estimated optimal treatment for each subject |
c |
the best regularization parameter C in SVM hinge loss or SVM ramp loss, chosen from the values specified in |
sigma |
the best parameter |
s |
the best slope parameter s in the ramp loss, chosen from the values specified in |
iter |
number of iterations under SVM ramp loss |
alpha1 |
the solution to the Lagrangian dual problem under SVM hinge loss or SVM ramp loss. It is used for constructing the decision function on the new sample. |
H |
the input H, returned only under SVM hinge loss with RBF kernel. It is used for constructing the RBF kernel on the new sample. |
Yuan Chen, Ying Liu, Donglin Zeng, Yuanjia Wang
Maintainer: Yuan Chen <[email protected]><[email protected]>
Liu, Y., Wang, Y., Kosorok, M., Zhao, Y., & Zeng, D. (2014). Robust hybrid learning for estimating personalized dynamic treatment regimens. arXiv preprint. arXiv, 1611.
Liu, Y., Wang, Y., Kosorok, M., Zhao, Y., & Zeng, D. (2018). Augmented Outcome-weighted Learning for Estimating Optimal Dynamic Treatment Regimens. Statistics in Medicine. In press.
Zhao, Y., Zeng, D., Rush, A. J., & Kosorok, M. R. (2012). Estimating individualized treatment rules using outcome weighted learning. Journal of the American Statistical Association, 107(499), 1106-1118.
Zhao, Y. Q., Zeng, D., Laber, E. B., & Kosorok, M. R. (2015). New statistical learning methods for estimating optimal dynamic treatment regimes. Journal of the American Statistical Association, 110(510), 583-598.
# simulate 2-stage training and test sets n_train = 100 n_test = 500 n_cluster = 10 pinfo = 10 pnoise = 20 train = sim_Kstage(n_train, n_cluster, pinfo, pnoise, K=2) H1_train = scale(train$X) H2_train = scale(cbind(H1_train, train$A[[1]], H1_train * train$A[[1]])) pi_train = list(rep(0.5, n_train), rep(0.5, n_train)) test = sim_Kstage(n_test, n_cluster, pinfo, pnoise, train$centroids, K=2) H1_test = scale(test$X) H2_test = scale(cbind(H1_test, test$A[[1]], H1_test * train$A[[1]])) pi_test = list(rep(0.5, n_test), rep(0.5, n_test)) # estimate DTR with owl on the training sample owl_train = owl(H=list(H1_train, H2_train), AA=train$A, RR=train$R, n=n_train, K=2, pi=pi_train, loss='hinge', augment=TRUE, m=3) owl_train$stage1$beta owl_train$stage1$treatment owl_train$valuefun # apply the estimated DTR to the test sample owl_test = predict(owl_train, H=list(H1_test, H2_test), AA=test$A, RR=test$R, K=2, pi=pi_test) owl_test$treatment owl_test$valuefun
# simulate 2-stage training and test sets n_train = 100 n_test = 500 n_cluster = 10 pinfo = 10 pnoise = 20 train = sim_Kstage(n_train, n_cluster, pinfo, pnoise, K=2) H1_train = scale(train$X) H2_train = scale(cbind(H1_train, train$A[[1]], H1_train * train$A[[1]])) pi_train = list(rep(0.5, n_train), rep(0.5, n_train)) test = sim_Kstage(n_test, n_cluster, pinfo, pnoise, train$centroids, K=2) H1_test = scale(test$X) H2_test = scale(cbind(H1_test, test$A[[1]], H1_test * train$A[[1]])) pi_test = list(rep(0.5, n_test), rep(0.5, n_test)) # estimate DTR with owl on the training sample owl_train = owl(H=list(H1_train, H2_train), AA=train$A, RR=train$R, n=n_train, K=2, pi=pi_train, loss='hinge', augment=TRUE, m=3) owl_train$stage1$beta owl_train$stage1$treatment owl_train$valuefun # apply the estimated DTR to the test sample owl_test = predict(owl_train, H=list(H1_test, H2_test), AA=test$A, RR=test$R, K=2, pi=pi_test) owl_test$treatment owl_test$valuefun
This function serves two purposes from a fitted "owl" object. It can recommend treatments for a new independent sample with partial or full subject features observed up to a certain stage. If subject feautures, treatment assignments and outcomes are fully observed in the new sample, this function can also evaluate the estimated DTR on this new sample, returning the empirical value function and benefit function.
## S3 method for class 'owl' predict(object, H, AA=NULL, RR=NULL, K, pi=NULL, ...)
## S3 method for class 'owl' predict(object, H, AA=NULL, RR=NULL, K, pi=NULL, ...)
object |
fitted "owl" object |
H |
subject history information before treatment at the |
AA |
observed treatment assignments at the |
RR |
observed outcomes at the |
K |
number of stages of |
pi |
treatment assignment probabilities of the observed treatments at the K stages for all subjects in the new sample. It is a vector if |
... |
further arguments passed to or from other methods. |
fit |
fitted decision functions at the K stages for each subject in the new sample. It is a list of K vectors. |
probability |
estimated probability that treatment 1 (vs. -1) is the optimal treatment at each stage for each subject in the new sample. It's calculated by exp(fit)/(1 + exp(fit)). It is a list of K vectors. |
treatment |
recommennded optimal treatments at the K stages for each subject in the new sample. It is a list of K vectors. |
valuefun |
overall empirical value function under the fitted DTR evaluated on the new sample. It is returned only when |
benefit |
overall empirical benefit function under the estimated DTR evaluated on the new sample. It is returned only when |
pi |
treatment assignment probabilities of the assigned treatments at the K stages for each subject in the new sample. If |
Yuan Chen, Ying Liu, Donglin Zeng, Yuanjia Wang
Maintainer: Yuan Chen <[email protected]><[email protected]>
owl
, sim_Kstage
, ql
# simulate 2-stage training and test sets n_train = 100 n_test = 500 n_cluster = 10 pinfo = 10 pnoise = 20 train = sim_Kstage(n_train, n_cluster, pinfo, pnoise, K=2) H1_train = scale(train$X) H2_train = scale(cbind(H1_train, train$A[[1]], H1_train * train$A[[1]])) pi_train = list(rep(0.5, n_train), rep(0.5, n_train)) test = sim_Kstage(n_test, n_cluster, pinfo, pnoise, train$centroids, K=2) H1_test = scale(test$X) H2_test = scale(cbind(H1_test, test$A[[1]], H1_test * train$A[[1]])) pi_test = list(rep(0.5, n_test), rep(0.5, n_test)) # estimate DTR with owl on the training sample owl_train = owl(H=list(H1_train, H2_train), AA=train$A, RR=train$R, n=n_train, K=2, pi=pi_train, loss='hinge', augment=TRUE, m=3) # evaluate the DTR when full information are observed on the new sample owl_test = predict(owl_train, H=list(H1_test, H2_test), AA=test$A, RR=test$R, K=2) owl_test$treatment owl_test$valuefun owl_test$pi # recommned the first-stage treatments only owl_test2 = predict(owl_train, H=H1_test, K=1) owl_test$treatment
# simulate 2-stage training and test sets n_train = 100 n_test = 500 n_cluster = 10 pinfo = 10 pnoise = 20 train = sim_Kstage(n_train, n_cluster, pinfo, pnoise, K=2) H1_train = scale(train$X) H2_train = scale(cbind(H1_train, train$A[[1]], H1_train * train$A[[1]])) pi_train = list(rep(0.5, n_train), rep(0.5, n_train)) test = sim_Kstage(n_test, n_cluster, pinfo, pnoise, train$centroids, K=2) H1_test = scale(test$X) H2_test = scale(cbind(H1_test, test$A[[1]], H1_test * train$A[[1]])) pi_test = list(rep(0.5, n_test), rep(0.5, n_test)) # estimate DTR with owl on the training sample owl_train = owl(H=list(H1_train, H2_train), AA=train$A, RR=train$R, n=n_train, K=2, pi=pi_train, loss='hinge', augment=TRUE, m=3) # evaluate the DTR when full information are observed on the new sample owl_test = predict(owl_train, H=list(H1_test, H2_test), AA=test$A, RR=test$R, K=2) owl_test$treatment owl_test$valuefun owl_test$pi # recommned the first-stage treatments only owl_test2 = predict(owl_train, H=H1_test, K=1) owl_test$treatment
This function serves two purposes from a fitted "ql" object. It can recommend treatments for a new independent sample with partial or full subject features observed up to a certain stage. If subject features, treatment assignments and outcomes are fully observed in the new sample, this function can also evaluate the fitted DTR on this new sample, returning the empirical value function and benefit function.
## S3 method for class 'ql' predict(object, H, AA=NULL, RR=NULL, K, pi=NULL, Qopt=FALSE, Qfit=FALSE, ...)
## S3 method for class 'ql' predict(object, H, AA=NULL, RR=NULL, K, pi=NULL, Qopt=FALSE, Qfit=FALSE, ...)
object |
fitted "ql" object |
H |
subject history information before treatment at the |
AA |
observed treatment assignments at the |
RR |
observed outcomes at the |
K |
number of stages of |
pi |
treatment assignment probabilities of the observed treatments at the K stages for all subjects in the new sample. It is a vector if |
Qopt |
whether to output the predicted optimal Q-function. The default is |
Qfit |
whether to output the estimated Q-function under the observed treatments. The default is |
... |
further arguments passed to or from other methods. |
treatment |
recommennded optimal treatments at the K stages for each subject in the new sample. It is a list of K vectors. If no tailoring variables are learned in the "ql" object, treatments will be assigned randomly with equal probability. |
valuefun |
overall empirical value function under the fitted DTR evaluated on the new sample. It is returned only when |
benefit |
overall empirical benefit function under the estimated DTR evaluated on the new sample. It is returned only when |
pi |
treatment assignment probabilities of the assigned treatments at the K stages for each subject in the new sample. If |
Q |
the predicted optimal Q-function if |
fitted |
the estimated Q-function under the observed treatment if |
Yuan Chen, Ying Liu, Donglin Zeng, Yuanjia Wang
Maintainer: Yuan Chen <[email protected]><[email protected]>
ql
, sim_Kstage
, owl
# simulate 2-stage training and test sets n_train = 100 n_test = 500 n_cluster = 10 pinfo = 10 pnoise = 20 train = sim_Kstage(n_train, n_cluster, pinfo, pnoise, K=2) H1_train = scale(train$X) H2_train = scale(cbind(H1_train, train$A[[1]], H1_train * train$A[[1]])) pi_train = list(rep(0.5, n_train), rep(0.5, n_train)) test = sim_Kstage(n_test, n_cluster, pinfo, pnoise, train$centroids, K=2) H1_test = scale(test$X) H2_test = scale(cbind(H1_test, test$A[[1]], H1_test * train$A[[1]])) pi_test = list(rep(0.5, n_test), rep(0.5, n_test)) # estimate DTR with ql on the training sample ql_train = ql(H=list(H1_train, H2_train), AA=train$A, RR=train$R, K=2, pi=pi_train, m=3) # evaluate the DTR when full information are observed on the new sample ql_test = predict(ql_train, H=list(H1_test, H2_test), AA=test$A, RR=test$R, K=2) ql_test$treatment ql_test$valuefun ql_test$pi # recommned the first-stage treatments only ql_test2 = predict(ql_train, H=H1_test, K=1) ql_test2$treatment
# simulate 2-stage training and test sets n_train = 100 n_test = 500 n_cluster = 10 pinfo = 10 pnoise = 20 train = sim_Kstage(n_train, n_cluster, pinfo, pnoise, K=2) H1_train = scale(train$X) H2_train = scale(cbind(H1_train, train$A[[1]], H1_train * train$A[[1]])) pi_train = list(rep(0.5, n_train), rep(0.5, n_train)) test = sim_Kstage(n_test, n_cluster, pinfo, pnoise, train$centroids, K=2) H1_test = scale(test$X) H2_test = scale(cbind(H1_test, test$A[[1]], H1_test * train$A[[1]])) pi_test = list(rep(0.5, n_test), rep(0.5, n_test)) # estimate DTR with ql on the training sample ql_train = ql(H=list(H1_train, H2_train), AA=train$A, RR=train$R, K=2, pi=pi_train, m=3) # evaluate the DTR when full information are observed on the new sample ql_test = predict(ql_train, H=list(H1_test, H2_test), AA=test$A, RR=test$R, K=2) ql_test$treatment ql_test$valuefun ql_test$pi # recommned the first-stage treatments only ql_test2 = predict(ql_train, H=H1_test, K=1) ql_test2$treatment
This function implements Q-learning for estimating general K-stage DTRs. Lasso penalty can be applied for variable selection at each stage.
ql(H, AA, RR, K, pi='estimated', lasso=TRUE, m=4)
ql(H, AA, RR, K, pi='estimated', lasso=TRUE, m=4)
H |
subject history information before treatment for all subjects at the |
AA |
observed treatment assignments for all subjects at the |
RR |
observed reward outcomes for all subjects at the |
K |
number of stages |
pi |
treatment assignment probabilities of the observed treatments for all subjects at the K stages. It is a vector if |
lasso |
specifies whether to add lasso penalty at each stage when fitting the model. The default is |
m |
number of folds in the |
A patient's history information prior to the treatment at stage k can be constructed recursively as with
, where
is subject-specific variables collected at stage k just prior to the treatment,
is the treatment at stage
, and
is the outcome observed post the treatment at stage
. Higher order or interaction terms can also be easily incorporated in
, e.g.,
.
A list of results is returned as an object. It contains the following attributes:
stage1 |
a list of stage 1 results, ... |
stageK |
a list of stage K results |
valuefun |
overall empirical value function under the estimated DTR |
benefit |
overall empirical benefit function under the estimated DTR |
pi |
treatment assignment probabilities of the assigned treatments for each subject at the K stages. If |
In each stage's result, a list is returned which consists of
co |
the estimated coefficients of |
treatment |
the estimated optimal treatment at this stage for each subject in the sample. If no tailoring variables are selected under lasso penalty, treatment will be assigned randomly with equal probability. |
Q |
the estimated optimal outcome increment from this stage to the end (the estimated optimal Q-function at this stage) for each subject in the sample |
Yuan Chen, Ying Liu, Donglin Zeng, Yuanjia Wang
Maintainer: Yuan Chen <[email protected]><[email protected]>
Watkins, C. J. C. H. (1989). Learning from delayed rewards (Doctoral dissertation, University of Cambridge).
Qian, M., & Murphy, S. A. (2011). Performance guarantees for individualized treatment rules. Annals of statistics, 39(2), 1180.
# simulate 2-stage training and test sets n_train = 100 n_test = 500 n_cluster = 10 pinfo = 10 pnoise = 20 train = sim_Kstage(n_train, n_cluster, pinfo, pnoise, K=2) H1_train = scale(train$X) H2_train = scale(cbind(H1_train, train$A[[1]], H1_train * train$A[[1]])) pi_train = list(rep(0.5, n_train), rep(0.5, n_train)) test = sim_Kstage(n_test, n_cluster, pinfo, pnoise, train$centroids, K=2) H1_test = scale(test$X) H2_test = scale(cbind(H1_test, test$A[[1]], H1_test * train$A[[1]])) pi_test = list(rep(0.5, n_test), rep(0.5, n_test)) ql_train = ql(H=list(H1_train, H2_train), AA=train$A, RR=train$R, K=2, pi=pi_train, m=3) ql_test = predict(ql_train, H=list(H1_test, H2_test), AA=test$A, RR=test$R, K=2, pi=pi_test)
# simulate 2-stage training and test sets n_train = 100 n_test = 500 n_cluster = 10 pinfo = 10 pnoise = 20 train = sim_Kstage(n_train, n_cluster, pinfo, pnoise, K=2) H1_train = scale(train$X) H2_train = scale(cbind(H1_train, train$A[[1]], H1_train * train$A[[1]])) pi_train = list(rep(0.5, n_train), rep(0.5, n_train)) test = sim_Kstage(n_test, n_cluster, pinfo, pnoise, train$centroids, K=2) H1_test = scale(test$X) H2_test = scale(cbind(H1_test, test$A[[1]], H1_test * train$A[[1]])) pi_test = list(rep(0.5, n_test), rep(0.5, n_test)) ql_train = ql(H=list(H1_train, H2_train), AA=train$A, RR=train$R, K=2, pi=pi_train, m=3) ql_test = predict(ql_train, H=list(H1_test, H2_test), AA=test$A, RR=test$R, K=2, pi=pi_test)
This function simulates a K-stage SMART data with (pinfo + pnoise)
baseline variables from a multivariate Gaussian distribution. The pinfo
variables have variance 1 and pairwise correlation 0.2; the pnoise
variables have mean 0 and are uncorrelated with each other and with the pinfo
variables.
Subjects are from n_cluster
latent groups with equal sizes, and these n_cluster
groups are characterized by their differentiable means in the pinfo
feature variables. Each latent group has its own optimal treatment sequence, where the optimal treatment for subjects in group g at stage k is generated as mod 2) - 1. The assigned treatment group (1 or -1) for each subject at each stage is randomly generated with equal probability. The primary outcome is observed only at the end of the trial, which is generated as
.
sim_Kstage (n, n_cluster, pinfo, pnoise, centroids=NULL, K)
sim_Kstage (n, n_cluster, pinfo, pnoise, centroids=NULL, K)
n |
sample size, should be a multiple of |
n_cluster |
number of latent groups |
pinfo |
number of informative baseline variables |
pnoise |
number of non-informative baseline variables |
centroids |
centroids of the |
K |
number of stages. |
X |
baseline variables. It is a matrix of dimension |
A |
treatment assigments for the K-stages. It is a list of K vectors. |
R |
outcomes of the K-stages. It is a list of K vectors. In this simulation setting, no intermediate outcomes are observed, so the first K-1 vectors are vectors of 0. |
optA |
optimal treatments for the K-stages. It is a list of K vectors. |
centroids |
centroids of the |
Yuan Chen, Ying Liu, Donglin Zeng, Yuanjia Wang
Maintainer: Yuan Chen <[email protected]><[email protected]>
n_train = 100 n_test = 500 n_cluster = 10 pinfo = 10 pnoise = 20 # simulate a 2-stage training set train = sim_Kstage(n_train, n_cluster, pinfo, pnoise, K=2) # simulate an independent 2-stage test set with the same centroids of the training set test = sim_Kstage(n_test, n_cluster, pinfo, pnoise, train$centroids, K=2)
n_train = 100 n_test = 500 n_cluster = 10 pinfo = 10 pnoise = 20 # simulate a 2-stage training set train = sim_Kstage(n_train, n_cluster, pinfo, pnoise, K=2) # simulate an independent 2-stage test set with the same centroids of the training set test = sim_Kstage(n_test, n_cluster, pinfo, pnoise, train$centroids, K=2)