Incremental propensity interventions#

This study validates three incremental treatment-odds multipliers, including the natural course at one. It compares cleverly with R npcausal at commit 56a5ac1 on identical samples. Kennedy (2019) publishes npcausal, and its influence values carry the derivative through the treatment mechanism. The comparison therefore gates inference as well as the point curve.

R imtp 0.1.0 held this role in an earlier revision and no longer does. Its reported influence curve omits that derivative, so it can witness the point curve and cannot gate a standard error. Choosing a comparator records the full survey.

Accuracy against known truth#

law

estimand

what was tested

implementation

bias (99% interval)

coverage

SE ratio

result

binary-outcome law with three incremental odds multipliers

ate_ipsi[odds x0.5 vs natural course]

difference in means under the incremental interventions “multiply the treatment odds by 0.5” against “leave the observed treatment mechanism unchanged”

cleverly

-0.000039 to 0.000378

0.9431

0.9932

pass

binary-outcome law with three incremental odds multipliers

ate_ipsi[odds x0.5 vs natural course]

difference in means under the incremental interventions “multiply the treatment odds by 0.5” against “leave the observed treatment mechanism unchanged”

R npcausal

-0.000187 to 0.000234

0.9444

0.9869

pass

binary-outcome law with three incremental odds multipliers

ate_ipsi[odds x2 vs natural course]

difference in means under the incremental interventions “multiply the treatment odds by two” against “leave the observed treatment mechanism unchanged”

cleverly

-0.000412 to 0.000034

0.9463

0.9986

pass

binary-outcome law with three incremental odds multipliers

ate_ipsi[odds x2 vs natural course]

difference in means under the incremental interventions “multiply the treatment odds by two” against “leave the observed treatment mechanism unchanged”

R npcausal

-0.000244 to 0.000209

0.9475

0.9889

pass

binary-outcome law with three incremental odds multipliers

ey_ipsi[natural course]

mean under the incremental intervention leave the observed treatment mechanism unchanged

cleverly

-0.000628 to 0.000839

0.9381

0.9824

pass

binary-outcome law with three incremental odds multipliers

ey_ipsi[natural course]

mean under the incremental intervention leave the observed treatment mechanism unchanged

R npcausal

-0.000628 to 0.000839

0.9381

0.9824

pass

binary-outcome law with three incremental odds multipliers

ey_ipsi[odds x0.5]

mean under the incremental intervention multiply the treatment odds by 0.5

cleverly

-0.000477 to 0.0010

0.9444

0.9885

pass

binary-outcome law with three incremental odds multipliers

ey_ipsi[odds x0.5]

mean under the incremental intervention multiply the treatment odds by 0.5

R npcausal

-0.000622 to 0.000881

0.9425

0.9895

pass

binary-outcome law with three incremental odds multipliers

ey_ipsi[odds x2]

mean under the incremental intervention multiply the treatment odds by two

cleverly

-0.000850 to 0.000683

0.9381

0.9762

pass

binary-outcome law with three incremental odds multipliers

ey_ipsi[odds x2]

mean under the incremental intervention multiply the treatment odds by two

R npcausal

-0.000681 to 0.000858

0.9363

0.9741

pass

Agreement with the canonical implementation#

Comparator-backed: a paired comparison with npcausal on the same samples. Each row reports estimate equivalence within the declared margin, the RMSE ratio and the coverage difference, and names its comparison kind.

law

estimand

what was compared

paired difference

share of margin used

RMSE ratio bound

coverage difference

comparison kind

calibration resolution

result

binary-outcome law with three incremental odds multipliers

ate_ipsi[odds x0.5 vs natural course]

difference in means under the incremental interventions “multiply the treatment odds by 0.5” against “leave the observed treatment mechanism unchanged”

0.000146

0.2993

0.9984

-0.0012

different estimator

0.0180 vs 0.0500

equivalent

binary-outcome law with three incremental odds multipliers

ate_ipsi[odds x2 vs natural course]

difference in means under the incremental interventions “multiply the treatment odds by two” against “leave the observed treatment mechanism unchanged”

-0.000172

0.3287

0.9944

-0.0012

different estimator

0.0254 vs 0.0500

equivalent

binary-outcome law with three incremental odds multipliers

ey_ipsi[natural course]

mean under the incremental intervention leave the observed treatment mechanism unchanged

6.730e-13

3.942e-10

1.0000

0

different estimator

4.226e-11 vs 0.0500

equivalent

binary-outcome law with three incremental odds multipliers

ey_ipsi[odds x0.5]

mean under the incremental intervention multiply the treatment odds by 0.5

0.000146

0.0834

1.0026

0.0019

different estimator

0.0019 vs 0.0500

equivalent

binary-outcome law with three incremental odds multipliers

ey_ipsi[odds x2]

mean under the incremental intervention multiply the treatment odds by two

-0.000172

0.0962

0.9993

0.0019

different estimator

0.0052 vs 0.0500

equivalent

Theory properties#

property

cell

role

what was tested

what must hold

measured

result

interval_calibration

contrast__correctly_specified

positive

odds-x2 contrast: both nuisances are correctly specified with an independently computed efficiency bound

SE ratio and coverage intervals both inside their calibration bands, with both efficiency-ratio intervals inside their bands

coverage 0.9421 to 0.9598, SE ratio 0.9778 to 1.0365, empirical efficiency ratio 0.9641 to 1.0221, reported efficiency ratio 0.9987 to 0.9997

pass

interval_calibration

contrast__noise_control

control

odds-x2 contrast: one efficiency-bound unit of independent noise is added to each estimate

the empirical efficiency ratio must rise above the band

coverage 0.8181 to 0.8486, SE ratio 0.6895 to 0.7295, empirical efficiency ratio 1.3696 to 1.4490, reported efficiency ratio 0.9987 to 0.9997

pass

interval_calibration

contrast__shrunken_se_control

control

odds-x2 contrast: the reported standard errors are multiplied by a declared factor below one

the SE-ratio interval must fall below the calibration band

coverage 0.8214 to 0.8518, SE ratio 0.6840 to 0.7256, empirical efficiency ratio 0.9642 to 1.0226, reported efficiency ratio 0.6991 to 0.6998

pass

mechanism_requirement

both_correct

positive

both the outcome regression and treatment mechanism are correctly specified

bias interval inside the equivalence margin

bias -0.000288 to 0.000233, margin 0.000875

pass

mechanism_requirement

mechanism_wrong

control

the wrong treatment mechanism is held fixed when the incremental target is evaluated

bias interval must fall entirely outside the margin

bias -0.0116 to -0.0112, margin 0.000627

pass

mechanism_requirement

outcome_wrong

positive

the treatment mechanism is correct and the outcome regression is misspecified

bias interval inside the equivalence margin

bias -0.000205 to 0.000306, margin 0.000857

pass

natural_course_identity

natural__ipsi

positive

natural course: the odds multiplier one is evaluated through the incremental axis

the paired estimate must equal the observed sample mean exactly

maximum paired difference 8.408e-11

pass

natural_course_identity

natural__mean

positive

natural course: the observed sample mean is retained as the identity control

the paired intervention estimate must equal it exactly

maximum paired difference 8.408e-11

pass

power

alternative

positive

the same test applied to a law with a real effect

rejection lower bound clears the minimum power

rejection 1, 0.9934 to 1

pass

root_n_and_efficiency

contrast__n_2000

positive

odds-x2 contrast: bias, coverage and SE calibration at n = 2,000

bias inside the margin, coverage clears the floor, SE ratio inside the sanity band

bias -0.000136, coverage 0.9416 to 0.9776, SE ratio 1.0402

pass

root_n_and_efficiency

contrast__n_500

control

odds-x2 contrast: bias, coverage and SE calibration at n = 500

coverage interval lies below nominal or clears the declared floor

bias -0.000560, coverage 0.9282 to 0.9688, SE ratio 1.0041

pass

root_n_and_efficiency

contrast__n_8000

positive

odds-x2 contrast: bias, coverage and SE calibration at n = 8,000

bias inside the margin, coverage clears the floor, SE ratio inside the sanity band

bias -0.000050, coverage 0.9297 to 0.9698, SE ratio 0.9987

pass

root_n_rate

contrast__empirical_sd

positive

odds-x2 contrast: log empirical spread of the estimates regressed on log n across three sizes

slope interval inside the root-n band and excluding -1/4

slope -0.5302 to -0.4656

pass

root_n_rate

contrast__reported_se

positive

odds-x2 contrast: the same regression applied to the mean reported standard error

slope interval inside the root-n band and excluding -1/4

slope -0.5003 to -0.4987

pass

targeting_necessity

mechanism__targeted

positive

treatment-mechanism targeting: the treatment mechanism is fluctuated after outcome targeting

bias interval inside the equivalence margin

bias -0.000313 to 0.000198, margin 0.000857

pass

targeting_necessity

mechanism__untargeted

control

treatment-mechanism targeting: the identical targeted outcome regression is evaluated at the unfluctuated mechanism

bias interval must fall entirely outside the margin

bias -0.0135 to -0.0130, margin 0.000870

pass

targeting_necessity

outcome__targeted

positive

outcome-regression targeting: the outcome regression is fluctuated before the incremental target is evaluated

bias interval inside the equivalence margin

bias -0.000421 to 0.000100, margin 0.000875

pass

targeting_necessity

outcome__untargeted

control

outcome-regression targeting: the identical targeted mechanism is evaluated with the initial outcome regression

bias interval must fall entirely outside the margin

bias -0.0904 to -0.0903, margin 0.000123

pass

treatment_score_necessity

odds_x2__full_eif

positive

odds-x2 incremental mean: the incremental mean uses the complete efficient influence curve

the reported-to-empirical SE-ratio interval must stay inside the declared band

SE ratio 0.9641 to 1.0547

pass

treatment_score_necessity

odds_x2__regime_curve_control

control

odds-x2 incremental mean: the same point estimates use an influence curve with the treatment-score term removed

the SE-ratio interval must fall below the calibration band

SE ratio 0.6077 to 0.6630

pass

type_i_error

sharp_null

positive

a confounded law whose true contrast is exactly zero

one-sided rejection bound stays under the declared type-I ceiling

rejection 0.0512, 0.0333 to 0.0748

pass

The property study tests the one-sided mechanism requirement, exact-EIF calibration, null and power controls, both targeting equations, the treatment-score term, and the natural-course identity.

Measured values and declared margins#

quantity

value

source

replicates

1600

paired replications

n

2000

observations per replication

independent_tests_passed

10

truth tests passing

independent_tests_total

10

truth tests reported

paired_tests_passed

5

paired comparisons passing

paired_tests_total

5

paired comparisons reported

property_cells_passed

21

property cells passing

property_cells_total

21

property cells reported

max_standardized_bias

0.0546

largest primary standardized bias

min_coverage

0.9363

lowest primary coverage

max_margin_utilization

0.3287

largest paired similarity-margin share

margin:confidence_level

0.9900

Monte Carlo confidence level

margin:alpha

0.0500

test size

margin:nominal_coverage

0.9500

nominal interval coverage

margin:bootstrap_replicates

10000

bootstrap replications

margin:standardized_bias

0.2500

standardized-bias margin

margin:coverage_floor

0.9000

primary coverage floor

margin:over_coverage_ceiling

0.9900

descriptive overcoverage threshold

margin:se_ratio_sanity_lower

0.8000

primary SE-ratio lower screen

margin:se_ratio_sanity_upper

1.2000

primary SE-ratio upper screen

margin:calibration_se_ratio_lower

0.9300

calibration SE-ratio lower bound

margin:calibration_se_ratio_upper

1.0700

calibration SE-ratio upper bound

margin:calibration_coverage_lower

0.9200

calibration coverage lower bound

margin:calibration_coverage_upper

0.9800

calibration coverage upper bound

margin:type_i_ceiling

0.1000

type-I upper bound

margin:paired_difference

0.1500

paired similarity margin in pooled SDs

margin:rmse_noninferiority

1.1000

RMSE-ratio noninferiority bound

margin:coverage_noninferiority

-0.0250

coverage-difference noninferiority bound

margin:calibration_noninferiority

0.0500

calibration-excess noninferiority bound

margin:minimum_power

0.8000

minimum power lower bound

margin:root_n_slope

-0.5000

expected root-n slope

margin:root_n_slope_lower

-0.6250

root-n slope lower bound

margin:root_n_slope_upper

-0.3750

root-n slope upper bound

margin:excluded_slope

-0.2500

slower rate the interval must exclude

margin:efficiency_ratio_lower

0.9000

efficiency-ratio lower bound

margin:efficiency_ratio_upper

1.1000

efficiency-ratio upper bound

margin:shrunken_se_factor

0.7000

negative-control SE multiplier

margin:targeting_displacement

0.2500

minimum targeting displacement

Limits#

  • The laws use binary treatment, binary outcome, and one three-level baseline covariate.

  • Both implementations saturate that covariate. cleverly fits one-hot indicators and their interaction with treatment. npcausal fits SL.glm.interaction over the same design. The treatment mechanism is supplied exactly to cleverly and is estimated by npcausal.

  • An earlier revision fitted the covariate as one numeric column. That model is misspecified, and it inflated the standard error of each contrast against the natural course by five to six percent above the exact-law efficient influence curve. Bias and coverage did not show it, because a correct mechanism keeps a targeted estimator consistent whatever the outcome model says. Consistency under a wrong outcome model is claimed by the mechanism_requirement property cells, which use exact nuisances and carry their own control.

  • npcausal cross-fits its nuisances over two folds and cleverly does not. The single-fold path that ?ipsi documents selects an empty training set and is not usable.

  • Only pointwise Wald inference is validated for either implementation.

  • The study covers ordinary, non-cross-fitted cleverly targeting and three fixed odds multipliers.

  • It excludes missing outcomes, weights, clusters, simultaneous bands, flexible learners, multinomial treatment, and longitudinal interventions. The default-band study measures the default band of this study’s subject fit.