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ORCID
https://orcid.org/0000-0001-9098-4805
Date of Graduation
5-11-2023
Semester of Graduation
Spring
Document Type
Thesis
Degree Name
Master of Arts (MA)
Department
Department of Graduate Psychology
Advisor(s)
Brian Leventhal
Yu Bao
Christine DeMars
Abstract
Response styles are consistent person-traits that are defined as the tendency to systematically select responses unrelated to the construct being measured (Paulhus, 1991). Response styles introduce construct-irrelevant variance that distorts observed scores on a measure and biases interpretation of the data. The current study looks at midpoint response style (MRS) and extreme response style (ERS). MRS is the tendency to select the midpoint of a rating scale, while ERS is the tendency to select the endpoints of a rating scale. Previous research sought to either account for response style effects or prevemt them – the current study does both. To account for response style effects, the current study used IRTree models which consists of multiple IRT models layered in a decision tree format. To prevent response style effects, the current study utilized secondary data that implemented two different item formats – traditional Likert items (control) and funnel items (experimental). The MCMC procedure in SAS 9.4 software was used to estimate model parameters. The primary analyses of the IRTree models used the EAP of the differences between the control and experimental group as well as the HPD intervals of the differences. The Likert item condition presented higher difficulty levels for the majority of items for the MRS and ERS stages of the IRTree models. This suggests that funnel items are potentially related to higher cases of midpoint and extreme response selections. In other words, Likert items are potentially related to lower cases of midpoint and extreme response selections. To determine which item format to implement, the costs and benefits for each item format should be assessed.
Recommended Citation
LeRoy, Stephanie, "Using IRTrees to account for response style effects between item formats" (2023). Masters Theses, 2020-current. 227.
https://commons.lib.jmu.edu/masters202029/227
