19,664 rated or chosen profiles from 1,229 respondents, in up to 8 tasks of 2 profiles varying on 7 attributes.

About this table

Description	Japanese adults (n = 1,229) compared two hypothetical politicians in each of 8 tasks (coalition with the JCP, tone, issue, age, career, gender, home prefecture) and chose which was more left-wing, liberal or progressive, the wording assigned between respondents (n = 406/414/409).
Reference	Ishima, H., Ashitani, K., & Okada, A. (2026). Confrontation, cooperation, and perceived ideology: Experimental research on voters' perceived positions and political competition. Japanese Journal of Political Science.
DOI	10.1017/S1468109926100449
Licence	CC0 1.0
Source data	https://doi.org/10.7910/DVN/IXR2EO

Notes

Conjoint table (irw_conjoint_2). Paired conjoint of hypothetical Japanese politicians (7 attributes, 8 tasks, fixed attribute order); forced choice of the politician perceived as more left / liberal / progressive, the wording assigned between respondents (trial_group); no opt-out. Level text is the authors' English codes, not the Japanese text shown; surname, IP and geolocation dropped.

These notes describe the source data, which the IRW reproduces as released. All notes are listed on the Data Notes page.

Size and shape

Respondents	1,229
Rows (one per respondent, task and profile)	19,664
Tasks per respondent (most)	8
Profiles per task	2
Attributes	7
Tasks with no profile chosen	0

Design

Topic	candidate choice
A profile represents	person
Country	JP
Language shown	ja
Language of stored levels	en
Randomization restrictions	unknown
Task order	recorded in the deposit
Profile position	recorded in the deposit

Outcomes:

choice	Which of the two politicians is more left-wing (left) / liberal (liberal) / progressive (prog)? One wording per respondent, in trial_group (paraphrase) [choice, forced]

Columns

attr_ageattr_careerattr_coalitionattr_genderattr_homeattr_issueattr_tonechoicecov_age_groupcov_educationcov_genderidprofiletasktrial_group

The layout (one row per respondent, task and profile; choice/rating outcomes; attr_ columns holding each attribute level as displayed) is defined in the IRW conjoint standard. What the outcomes asked is under Design above.

Get the data

Download CSVno account needed Browse on Redivisexplore and query Croissant metadataHugging Face, Kaggle, OpenML

Or load it directly in R or Python (both need a free Redivis account; the first call opens a browser to sign in):

# R
install.packages("remotes")
remotes::install_github("itemresponsewarehouse/Rpkg")
library(irw)
df <- irw_fetch("ishima_2026_perceived_ideology", source = "conj")

# Python
pip install irw

import irw
df = irw.fetch("ishima_2026_perceived_ideology", source="conj")

How to cite

@article{Ishima_2026, title={Confrontation, cooperation, and perceived ideology: experimental research on voters’ perceived positions and political competition}, ISSN={1474-0060}, url={http://dx.doi.org/10.1017/S1468109926100449}, DOI={10.1017/s1468109926100449}, journal={Japanese Journal of Political Science}, publisher={Cambridge University Press (CUP)}, author={Ishima, Hideo and Ashitani, Keisuke and Okada, Ashu}, year={2026}, month=Sept, pages={1–15} }

Version and provenance

IRW version	v584
Redivis dataset	irw_conjoint_2 v1.4
Redivis dataset DOI	10.57761/hk97-wv30
Manifest pin for this IRW version	v1.4
Metadata source	irw_meta v44.0