himmelstein-impossible_question-2025

70,103 responses from 1,194 respondents to 90 items.

About this table

DescriptionThis dataset measures performance on a mix of general-knowledge and impossible.
ReferenceHimmelstein, Mark, Sophie Ma Zhu, Nikolay Petrov, Ezra Karger, Jessica Helmer, Sivan Livnat, Amory Bennett, Page Hedley, and Phil Tetlock. “The Forecasting Proficiency Test: A General Use Assessment of Forecasting Ability”. PsyArXiv, November 23, 2025. doi:10.31234/osf.io/a7kdx_v8.
DOI10.31234/osf.io/a7kdx_v8
LicenceCC BY 4.0
Source datahttps://github.com/forecastingresearch/fpt/tree/main/data_cognitive_tasks

Size and shape

Responses70,103
Respondents1,194
Items90
Response categories2
Responses per respondent58.713
Responses per item778.922
Density0.652
LongitudinalTRUE

Classification

age rangeAdult (18+)
construct typeCognitive/educational
measurement toolTest
item formatLikert Scale/selected response
primary language(s)eng
construct namePerformance on a mix of general-knowledge and impossible (unknowable) questions

Item text

This table has item text in the IRW: the wording administered to respondents, not just the response codes.

InstrumentThis dataset measures accuracy on a two-alternative forced-choice general-knowledge task that also contains unanswerable ('impossible') questions, on which the correct response is to opt out.
Mean words per item10.600
Mean characters per item60.967
Mean characters per response2
Flesch-Kincaid grade level6.682

Columns

cov_session_ididitemresprtwave

Get the data

Download CSVno account neededBrowse on Redivisexplore and queryCroissant metadataHugging Face, Kaggle, OpenML

Or load it directly in R or Python:

# R
install.packages("remotes")
remotes::install_github("itemresponsewarehouse/Rpkg")
library(irw)
df <- irw_fetch("himmelstein-impossible_question-2025")
# Python
pip install irw

import irw
df = irw.fetch("himmelstein-impossible_question-2025")

Version and provenance

IRW versionv393
Redivis datasetitem_response_warehouse_2 v19.0
Redivis dataset DOI10.57761/qtx5-4m80
Manifest pin for this IRW versionv19.0
Metadata sourceirw_meta v23.0