Author
Listed:
- Shiraito, Yuki
- Lo, James
- Olivella, Santiago
Abstract
A common approach when studying the quality of representation involves comparing the latent preferences of voters and legislators, commonly obtained by fitting an item response theory (IRT) model to a common set of stimuli. Despite being exposed to the same stimuli, voters and legislators may not share a common understanding of how these stimuli map onto their latent preferences, leading to differential item functioning (DIF) and incomparability of estimates. We explore the presence of DIF and incomparability of latent preferences obtained through IRT models by reanalyzing an influential survey dataset, where survey respondents expressed their preferences on roll call votes that U.S. legislators had previously voted on. To do so, we propose defining a Dirichlet process prior over item response functions in standard IRT models. In contrast to typical multistep approaches to detecting DIF, our strategy allows researchers to fit a single model, automatically identifying incomparable subgroups with different mappings from latent traits onto observed responses. We find that although there is a group of voters whose estimated positions can be safely compared to those of legislators, a sizeable share of surveyed voters understand stimuli in fundamentally different ways. Ignoring these issues can lead to incorrect conclusions about the quality of representation.
Suggested Citation
Shiraito, Yuki & Lo, James & Olivella, Santiago, 2023.
"A Nonparametric Bayesian Model for Detecting Differential Item Functioning: An Application to Political Representation in the US,"
Political Analysis, Cambridge University Press, vol. 31(3), pages 430-447, July.
Handle:
RePEc:cup:polals:v:31:y:2023:i:3:p:430-447_11
Download full text from publisher
Corrections
All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:cup:polals:v:31:y:2023:i:3:p:430-447_11. See general information about how to correct material in RePEc.
If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.
We have no bibliographic references for this item. You can help adding them by using this form .
If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.
For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: Kirk Stebbing (email available below). General contact details of provider: https://www.cambridge.org/pan .
Please note that corrections may take a couple of weeks to filter through
the various RePEc services.