On the instrumental variable estimation with many weak and invalid instruments

We discuss the fundamental issue of identification in linear instrumental variable (IV) models with unknown IV validity. With the assumption of the ‘sparsest rule’, which is equivalent to the plurality rule but becomes operational in computation algorithms, we investigate and prove the advantages of...

Full description

Bibliographic Details
Main Authors: Lin, Y, Windmeijer, F, Song, X, Fan, Q
Format: Journal article
Language:English
Published: Oxford University Press 2024
_version_ 1824458694511820800
author Lin, Y
Windmeijer, F
Song, X
Fan, Q
author_facet Lin, Y
Windmeijer, F
Song, X
Fan, Q
author_sort Lin, Y
collection OXFORD
description We discuss the fundamental issue of identification in linear instrumental variable (IV) models with unknown IV validity. With the assumption of the ‘sparsest rule’, which is equivalent to the plurality rule but becomes operational in computation algorithms, we investigate and prove the advantages of non-convex penalized approaches over other IV estimators based on two-step selections, in terms of selection consistency and accommodation for individually weak IVs. Furthermore, we propose a surrogate sparsest penalty that aligns with the identification condition and provides oracle sparse structure simultaneously. Desirable theoretical properties are derived for the proposed estimator with weaker IV strength conditions compared to the previous literature. Finite sample properties are demonstrated using simulations and the selection and estimation method is applied to an empirical study concerning the effect of body mass index on diastolic blood pressure.
first_indexed 2024-03-07T08:27:37Z
format Journal article
id oxford-uuid:6d706a92-bfcb-48d6-818f-93f73d2837c8
institution University of Oxford
language English
last_indexed 2025-02-19T04:29:58Z
publishDate 2024
publisher Oxford University Press
record_format dspace
spelling oxford-uuid:6d706a92-bfcb-48d6-818f-93f73d2837c82024-12-17T09:31:47ZOn the instrumental variable estimation with many weak and invalid instrumentsJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:6d706a92-bfcb-48d6-818f-93f73d2837c8EnglishSymplectic ElementsOxford University Press2024Lin, YWindmeijer, FSong, XFan, QWe discuss the fundamental issue of identification in linear instrumental variable (IV) models with unknown IV validity. With the assumption of the ‘sparsest rule’, which is equivalent to the plurality rule but becomes operational in computation algorithms, we investigate and prove the advantages of non-convex penalized approaches over other IV estimators based on two-step selections, in terms of selection consistency and accommodation for individually weak IVs. Furthermore, we propose a surrogate sparsest penalty that aligns with the identification condition and provides oracle sparse structure simultaneously. Desirable theoretical properties are derived for the proposed estimator with weaker IV strength conditions compared to the previous literature. Finite sample properties are demonstrated using simulations and the selection and estimation method is applied to an empirical study concerning the effect of body mass index on diastolic blood pressure.
spellingShingle Lin, Y
Windmeijer, F
Song, X
Fan, Q
On the instrumental variable estimation with many weak and invalid instruments
title On the instrumental variable estimation with many weak and invalid instruments
title_full On the instrumental variable estimation with many weak and invalid instruments
title_fullStr On the instrumental variable estimation with many weak and invalid instruments
title_full_unstemmed On the instrumental variable estimation with many weak and invalid instruments
title_short On the instrumental variable estimation with many weak and invalid instruments
title_sort on the instrumental variable estimation with many weak and invalid instruments
work_keys_str_mv AT liny ontheinstrumentalvariableestimationwithmanyweakandinvalidinstruments
AT windmeijerf ontheinstrumentalvariableestimationwithmanyweakandinvalidinstruments
AT songx ontheinstrumentalvariableestimationwithmanyweakandinvalidinstruments
AT fanq ontheinstrumentalvariableestimationwithmanyweakandinvalidinstruments