help opl_frontier_tb

Title

opl_frontier_tb - Postestimation frontiers for threshold-based optimal policy learning

Syntax

opl_frontier_tb
[,
frame(name)
saving(filename)
graph
bands(#)
splinepoints(#)
grsize(#)
replace]

Description

opl_frontier_tb is a postestimation command for
opl_cba_tb. It extracts the candidate-policy grid stored in
e(grid), creates a Stata frame containing all candidate threshold
policies, identifies efficient policies, and optionally produces graphical
representations of the policy frontier.

The command computes both the cost-benefit efficient frontier and the
cost-surplus efficient frontier and provides graphical summaries of the
trade-offs among treatment coverage, treatment benefit, treatment cost,
and weighted welfare.

Remarks

The variable supplied as tauvar should contain estimated causal treatment
effects. These may be obtained using cate, make_cate, or
another valid CATE estimator. The command does not estimate treatment effects
internally.

Threshold policies are deliberately restrictive. Their main advantage is
interpretability: treatment assignment can be expressed using one or two
observable cutoff rules. The difference between e(Q_fb) and
e(Q_opt) measures the welfare cost of imposing this interpretable policy
class.

The threshold direction is always upper: observations are treated when each
standardized selection variable is greater than or equal to its threshold.

Because selection variables are standardized internally, values supplied in
custom() refer to the [0,1] scale rather than the variables' original
units.

Example

Load the example dataset and estimate a one-threshold welfare-maximizing
policy:

sysuse data_opl_tb_cba_2, clear

local lambda = 0.60

opl_tb_cba tau, cost(cost) select(x1) lambda(`lambda') npoints(101) custom(.30 .50 .70) custompolicy(D) generate(opl1) graph replace

Inspect the estimation results and the grid of candidate policies:

ereturn list

matrix list e(grid)

Construct and graph the policy frontiers:

opl_frontier_tb, frame(welfare_frontier) saving(welfare_frontier.dta) graph grsize(0.8) replace

Open the frontier frame:

frame change welfare_frontier

Return to the default frame:

frame change default

Acknowledgment

The development of this software was supported by FOSSR (Fostering Open
Science in Social Science Research), a project funded by the European Union -
NextGenerationEU under the NPRR Grant agreement n. MURIR0000008.

Author

Giovanni Cerulli

IRCrES-CNR

Research Institute for Sustainable Economic Growth,
National Research Council of Italy

E-mail: giovanni.cerulli@cnr.it

Also see

Online: opl