0

我正在Card et al Medicare 数据上实施 RDDtools 包。我已经能够建立一个简单的参数回归。我现在想做的是在ageyrs. 我ageyrs作为协变量输入,但返回错误:

library(rddtools)
load(file ="C:/Users/perdue/Desktop/Adv.MicroEconometrics/HA 9/medicare.Rdata")

rd.medic<-rdd_data(y=er,x=ageyrs, covar=ageyrs, cutpoint=65, data = medicare)

rd.reg <- rdd_reg_lm(rdd_object=rd.medic, covariates = rd.medic$ageyrs, slope =("same"), covar.opt = ("include"))

    Error: $ operator is invalid for atomic vectors
4.
match.arg(covar.opt$strategy, choices = c("include", "residual"))
3.
model.matrix.rdd_data(rdd_object, covariates = covariates, order = order, bw = bw, slope = slope, covar.opt = covar.opt)
2.
model.matrix(rdd_object, covariates = covariates, order = order, bw = bw, slope = slope, covar.opt = covar.opt)
1.
rdd_reg_lm(rdd_object = rd.medic, covariates = rd.medic$ageyrs, slope = ("same"), covar.opt = ("include"))

文档中,它说我应该将协变量作为公式输入。有谁知道这个公式是什么?

4

1 回答 1

2

问题可能是covar.opt必须是一个列表。这没有产生任何错误:

rd.reg <- rdd_reg_lm(rdd_object=rd.medic, covariates = 'ageyrs', slope =
("same"), covar.opt = list("include"))
于 2018-01-18T09:20:19.197 回答