plot.qLearnS1: Residual plots for the first-stage regression

In iqLearn: Interactive Q-Learning

Description

Displays common residual plots based on the model for the first-stage regression in Q-learning. Due to the response being a non-smooth, non-monotone transformation of the data, these plots may not be meaningful.

Usage

## S3 method for class 'qLearnS1'
plot(x, ...)

Arguments

x	object of type qLearnS1
...	additional arguments to be passed to plot()

Value

None.

Author(s)

Kristin A. Linn <[e-mail]>, Eric B. Laber, Leonard A. Stefanski

References

Linn, K. A., Laber, E. B., Stefanski, L. A. (2015) "iqLearn: Interactive Q-Learning in R", Journal of Statistical Software, 64(1), 1–25.

Laber, E. B., Linn, K. A., and Stefanski, L. A. (2014) "Interactive model building for Q-learning", Biometrika, 101(4), 831-847.

See Also

qLearnS1

Examples

## load in two-stage BMI data
data (bmiData)
bmiData$A1[which (bmiData$A1=="MR")] = 1
bmiData$A1[which (bmiData$A1=="CD")] = -1
bmiData$A2[which (bmiData$A2=="MR")] = 1
bmiData$A2[which (bmiData$A2=="CD")] = -1
bmiData$A1 = as.numeric (bmiData$A1)
bmiData$A2 = as.numeric (bmiData$A2)
s1vars = bmiData[,1:4]
s2vars = bmiData[,c (1, 3, 5)]
a1 = bmiData[,7]
a2 = bmiData[,8]
## define response y to be the negative 12 month change in BMI from
## baseline 
y = -(bmiData[,6] - bmiData[,4])/bmiData[,4]
## second-stage regression
fitQ2 = qLearnS2 (y ~ gender + parent_BMI + month4_BMI +
  A2*(parent_BMI + month4_BMI), data=bmiData, "A2", c("parent_BMI",
                                  "month4_BMI"))
## first-stage regression
fitQ1 = qLearnS1 (~ gender + race + parent_BMI + baseline_BMI +
  A1*(gender + parent_BMI), data=bmiData, "A1", c ("gender",
                              "parent_BMI"), fitQ2)
plot (fitQ1)

iqLearn documentation built on May 2, 2019, 6:44 a.m.