Conditional as-if analyses in randomized experiments

The injunction to “analyze the way you randomize” is well known to statisticians since Fisher advocated for randomization as the basis of inference. Yet even those convinced by the merits of randomization-based inference seldom follow this injunction to the letter. Bernoulli randomized experiments a...

Full description

Bibliographic Details
Main Authors: Pashley Nicole E., Basse Guillaume W., Miratrix Luke W.
Format: Article
Language:English
Published: De Gruyter 2021-12-01
Series:Journal of Causal Inference
Subjects:
Online Access:https://doi.org/10.1515/jci-2021-0012
_version_ 1798030171494678528
author Pashley Nicole E.
Basse Guillaume W.
Miratrix Luke W.
author_facet Pashley Nicole E.
Basse Guillaume W.
Miratrix Luke W.
author_sort Pashley Nicole E.
collection DOAJ
description The injunction to “analyze the way you randomize” is well known to statisticians since Fisher advocated for randomization as the basis of inference. Yet even those convinced by the merits of randomization-based inference seldom follow this injunction to the letter. Bernoulli randomized experiments are often analyzed as completely randomized experiments, and completely randomized experiments are analyzed as if they had been stratified; more generally, it is not uncommon to analyze an experiment as if it had been randomized differently. This article examines the theoretical foundation behind this practice within a randomization-based framework. Specifically, we ask when is it legitimate to analyze an experiment randomized according to one design as if it had been randomized according to some other design. We show that a sufficient condition for this type of analysis to be valid is that the design used for analysis should be derived from the original design by an appropriate form of conditioning. We use our theory to justify certain existing methods, question others, and finally suggest new methodological insights such as conditioning on approximate covariate balance.
first_indexed 2024-04-11T19:37:00Z
format Article
id doaj.art-1d0c28b3add04910b9a2c5da2ccb68b8
institution Directory Open Access Journal
issn 2193-3685
language English
last_indexed 2024-04-11T19:37:00Z
publishDate 2021-12-01
publisher De Gruyter
record_format Article
series Journal of Causal Inference
spelling doaj.art-1d0c28b3add04910b9a2c5da2ccb68b82022-12-22T04:06:49ZengDe GruyterJournal of Causal Inference2193-36852021-12-019126428410.1515/jci-2021-0012Conditional as-if analyses in randomized experimentsPashley Nicole E.0Basse Guillaume W.1Miratrix Luke W.2Department of Statistics, Rutgers University, Piscataway, NJ 08854, United States of AmericaDepartment of Statistics, Stanford University, Stanford, CA 94305, United States of AmericaHarvard Graduate School of Education, Cambridge, MA 02138, United States of AmericaThe injunction to “analyze the way you randomize” is well known to statisticians since Fisher advocated for randomization as the basis of inference. Yet even those convinced by the merits of randomization-based inference seldom follow this injunction to the letter. Bernoulli randomized experiments are often analyzed as completely randomized experiments, and completely randomized experiments are analyzed as if they had been stratified; more generally, it is not uncommon to analyze an experiment as if it had been randomized differently. This article examines the theoretical foundation behind this practice within a randomization-based framework. Specifically, we ask when is it legitimate to analyze an experiment randomized according to one design as if it had been randomized according to some other design. We show that a sufficient condition for this type of analysis to be valid is that the design used for analysis should be derived from the original design by an appropriate form of conditioning. We use our theory to justify certain existing methods, question others, and finally suggest new methodological insights such as conditioning on approximate covariate balance.https://doi.org/10.1515/jci-2021-0012ancillary statisticscausal inferenceconditional inferencerandomization inferencerelevance62d9962k99
spellingShingle Pashley Nicole E.
Basse Guillaume W.
Miratrix Luke W.
Conditional as-if analyses in randomized experiments
Journal of Causal Inference
ancillary statistics
causal inference
conditional inference
randomization inference
relevance
62d99
62k99
title Conditional as-if analyses in randomized experiments
title_full Conditional as-if analyses in randomized experiments
title_fullStr Conditional as-if analyses in randomized experiments
title_full_unstemmed Conditional as-if analyses in randomized experiments
title_short Conditional as-if analyses in randomized experiments
title_sort conditional as if analyses in randomized experiments
topic ancillary statistics
causal inference
conditional inference
randomization inference
relevance
62d99
62k99
url https://doi.org/10.1515/jci-2021-0012
work_keys_str_mv AT pashleynicolee conditionalasifanalysesinrandomizedexperiments
AT basseguillaumew conditionalasifanalysesinrandomizedexperiments
AT miratrixlukew conditionalasifanalysesinrandomizedexperiments