gpt {meta.shrinkage}R Documentation

The General Pretest (GPT) Estimator for Sparse Means

Description

This function is used to calculate the general pretest (GPT) estimator for individual means under sparse means. As an option, confidence intervals corresponding to pretest estimators can be computed. The methodology is described in detail in Section 3.3 of Taketomi et al. (2021), Section 3.4 of Taketomi et al. (2022), and Section 2 and Section 3 of Taketomi et al. (2023-). An example shows the application of this method to the gastric cancer data of GASTRIC group (2013) .

Usage

gpt(y,s,alpha1=0.05,alpha2=0.10,level=0.05,q=0.5,conf.int=FALSE,conf.type="pivot")

Arguments

y

a vector for estimates

s

a vector for standard errors of y

alpha1

significance level for pretest (0<alpha1<1)

alpha2

significance level for pretest (0<alpha2<1)

level

a constant such that 1-level is confidence level

q

degrees of shrinkage(0<q<1)

conf.int

an indicator whether confidence intervals for pretest estimators are in the output

conf.type

an indicator that implies which type of confidence intervals for pretest estimators is in the output. Default is "pivot".The other type is "wald".

Value

PT

pretest(PT) estimator for y

GPT

general pretest(GPT) estimator for y

lower.pt.pivot

Lower limits for pivoting type.

upper.pt.pivot

Upper limits for pivoting type.

lower.pt.wald

Lower limits for Wald type.

upper.pt.wald

Upper limits for Wald type.

Author(s)

Nanami Taketomi, Takeshi Emura

References

Taketomi N, Konno Y, Chang YT and Emura T (2021). A meta-analysis for simultaneously estimating individual means with shrinkage, isotonic regression and pretests. Axioms. 10. 267. 10.3390/axioms10040267.

Taketomi N, Michimae H, Chang YT and Emura T (2022). meta.shrinkage: An R Package for Meta-Analyses for Simultaneously Estimating Individual Means. Algorithms. 15. 26.

Taketomi N, Chang YT, Konno Y, Mori M and Emura T (2023-). Confidence interval for normal means in meta-analysis based on a pretest estimator. Under review.

GASTRIC group (2013). Role of chemotherapy for advanced/recurrent gastric cancer: An individual-patient-data meta-analysis, European Journal of Cancer 49 (7): 1565-1577. doi:10.1016/j.ejca.2012.12.016.

Examples

#Estimates from the gastric cancer studies(Taketomi et al.(2021); GASTRIC group (2013))
y<-c(-0.18312,-0.72266,-0.48507,-0.23961,-0.13226,-0.27228,-0.5867,-0.13969,
-0.1004,-0.31143,-0.04949,-0.11685,-0.13044,0.04391)

#Standard errors(Taketomi et al.(2021))
s<-c(0.15372,0.28686,0.33192,0.21558,0.14691,0.14416,0.24885,
0.14542,0.16404,0.17038,0.19818,0.16476,0.19268,0.17632)

#Pretest(PT) estimator and general pretest(GPT) estimator
gpt(y,s)

#If conf.int=TRUE, confidence intervals fot PT are in the output.
#Default is 95% confidence interval in pivot type.
gpt(y,s,conf.int=TRUE)


[Package meta.shrinkage version 0.1.4 Index]