osterdelstar function

Computes delta* according to Oster (2019)

osterdelstar(parameters, Rmax)

Arguments

• parameters: A vector of parameters that is generated after estimating the short, intermediate and auxiliary regressions.
• Rmax: A real number that lies between Rtilde (R-squared for the intermediate regression) and 1.

Returns

A data frame with three columns:

• delstar: The value of delta for the chosen value of Rmax

• discontinuity: Indicates whether the point of discontinuity is within the interval formed by Rtilde and 1

• slope: Slope of the function, delta=f(Rmax)

Examples

## Load data set
data("NLSY_IQ")
 
## Set age and race as factor variables
NLSY_IQ$age <- factor(NLSY_IQ$age)
NLSY_IQ$race <- factor(NLSY_IQ$race)
   
## Collect parameters from the short, intermediate and auxiliary regressions
parameters <- collect_par(
data = NLSY_IQ, outcome = "iq_std", 
treatment = "BF_months", 
control = c("age","sex","income","motherAge","motherEDU","mom_married","race"),
other_regressors = c("sex","age"))

## Oster's method: delta* (for Rmax=0.61)
osterdelstar(parameters = parameters, Rmax=0.61)