Social Cognition
Bias Blind Spot Task
Also called: bias blind spot effect, blind spot bias, self-other asymmetry in perceived bias, perceived bias in self and others
Measure the bias blind spot: participants read short descriptions of common habits of thinking and rate how much each applies to them and to the average person their age.
5-7 minUntimed
Free to start: 10 free participants per account, then $0.99 per participant for academic research, or any yearly plan. Try it here first, with no account.
- Papers, 2021 to 2025
- 89
- Evidence grade
- D
- Registered clinical studies
- 0
What it measures
Measures the bias blind spot. Participants read short descriptions of 12 common habits of thinking, such as feeling after the fact that one knew all along how something would end, and of 4 everyday shortcomings, and rate how much each applies to them and to the average person their age. The main score is how much more the habits are seen in others than in oneself.
Constructs
- Bias blind spot
- Naive realism
- Introspection illusion
- Self-other asymmetry
Research uses
- Social cognition research
- Judgment and decision-making research
- Debiasing and training research
- Within-study group comparison
How the paradigm works
The bias blind spot task measures the bias blind spot: people see common habits of thinking more in others than in themselves. Pronin, Lin and Ross (2002) described biases, such as explaining one's successes by one's own qualities and one's failures by circumstances, and personal shortcomings, such as fear of public speaking, and asked people how much they and others showed each. People rated themselves as less subject to the biases than the average American, classmates in a seminar and fellow airport travelers, while on the shortcomings they saw themselves as just as flawed as their peers, if not more so. In three replications with 969 participants, Chandrashekar and colleagues (2021) found the blind spot for biases (d = -1.00 for oneself against others) and a smaller one for shortcomings (d = -0.34). Scopelliti and colleagues (2015) built a 14-item scale of the same form: each bias described as a tendency, then rated for oneself and for the average American from 1 (not at all) to 7 (very much), and scored as the average American's rating minus one's own. Across five samples of 661 people, the mean was 1.48, and 85.2% of them showed a significant blind spot. Higher cognitive ability does not shrink it (West, Meserve and Stanovich, 2012).
More about the paradigm
Here, participants read 16 descriptions written for this task: 12 habits of thinking, such as feeling after a match that one knew all along how it would end, and 4 everyday shortcomings, such as putting off unpleasant tasks. Each description is followed by two questions on two screens: how much it applies to the participant, and how much it applies to the average person their age, from 1 (not at all) to 7 (very much). Which question comes first is drawn from the session's seed and kept for every description, so half of the sessions start with each, unless the study fixes it; the order of the descriptions is drawn too. Each description says what some people do, in one or two plain sentences without the words bias or error, and none concerns politics, religion, health, crime, money advice or a group of people; none is an item of Pronin and colleagues or of Scopelliti and colleagues. The descriptions are written in each of the eight languages. One practice description comes first, and there is no time limit.
The main score is the blind spot: the average person's rating minus the participant's own, averaged over the 12 habits of thinking, from -6 to 6. The same difference over the 4 shortcomings, and the blind spot beyond it, separate seeing bias in others from rating oneself well in general, as Pronin and colleagues' comparison did. The mean ratings for oneself and for the average person and the share of habits seen more in others come with it. Scores describe how people rate themselves beside the average person their age; they are research measures for comparing groups, and they do not show how biased a person is and do not diagnose.
Scores
- Blind Spotscore
- Over the habits of thinking rated for both, the average person's rating minus the participant's own, from -6 to 6.
- Positive means the habits were seen more in the average person their age than in oneself, the bias blind spot
- Gap on Shortcomingsscore
- Over the everyday shortcomings, the average person's rating minus the participant's own.
- A smaller gap than for the habits of thinking is expected
- Blind Spot Beyond Shortcomingsscore
- The blind spot minus the gap on shortcomings.
- Positive means habits of thinking were seen in others more than shortcomings were, beyond rating oneself well in general
- Own Rating of the Habitsscore
- Mean rating of how much the habits of thinking apply to the participant, from 1 to 7.
- Informational
- Average Person's Rating of the Habitsscore
- Mean rating of how much the habits of thinking apply to the average person their age, from 1 to 7.
- Informational
- Habits Seen More in Others%
- The share of habits of thinking rated higher for the average person than for the participant.
- Informational
- Median Rating Timems
- Median time from a rating screen appearing to a rating, over ratings at or after 100 ms.
- Informational
- Ratings Under 100 mscount
- Ratings made less than 100 ms after their screen appeared.
- 0 expected
- Descriptions Rated for Bothcount
- Descriptions rated for the participant and for the average person, out of 16.
- Informational
Use and evidence
89 papers from 2021 to 2025 name this task in their title or abstract, up 75% compared with 2016 to 2020. That ranks it 276 of 632 test families in our census. See the counts for every test.
Show the numbers
| Year | Papers |
|---|---|
| 2025 | 34 |
| 2024 | 11 |
| 2023 | 16 |
| 2022 | 17 |
| 2021 | 11 |
| 2020 | 10 |
| 2019 | 11 |
| 2018 | 8 |
| 2017 | 11 |
| 2016 | 11 |
| 2015 | 10 |
| 2014 | 7 |
| 2013 | 5 |
| 2012 | 6 |
| 2011 | 4 |
| 2010 | 1 |
| 2009 | 1 |
| 2008 | 0 |
| 2007 | 1 |
| 2006 | 3 |
| 2005 | 1 |
| 2004 | 2 |
| 2003 | 1 |
| 2002 | 1 |
| 2001 | 0 |
| 2000 | 0 |
Use grade D
30 to 99 papers from 2021 to 2025.
Evidence grade D
Little published measurement evidence found.
- Papers on test-retest reliability
- 1
- Papers on reliability or validity
- 11
- Registered clinical studies using it as an outcome
- 0
Measured on ConductCognition
Pooled across the studies that feed our platform norms, by device group. A figure needs 50 or more people.
No pooled figure yet.
Note on the counts: includes essays that discuss the bias without measuring it.
How the grades work
Use: A is 1,000 or more papers from 2021 to 2025, B 300 to 999, C 100 to 299, D 30 to 99 and E fewer than 30. Evidence: A means at least 25 papers report its test-retest reliability and at least 25 registered clinical studies use it as an outcome; B, at least 8 test-retest papers, and either 5 registered clinical studies or 150 reliability or validity papers; C, at least 2 test-retest papers, 30 reliability or validity papers or 3 registered clinical studies; D, little published measurement evidence found. The counts measure use. They include every paper that names the task in its title or abstract. Grades describe the published research on this task, not ConductCognition's version of it.
Source: ConductCognition test census 0.44.0, counted 12 November 2026 from OpenAlex and ClinicalTrials.gov.
Task design
The trial sequence as the test runs in ConductCognition.
- Descriptions
- 16 written for this task: 12 habits of thinking, such as feeling after a match that one knew all along how it would end, and 4 everyday shortcomings, such as putting off unpleasant tasks. Each says what some people do, in one or two plain sentences without the words bias or error; none has political, religious, health, crime, money advice or group content, and none is a published item. They are shown in the session's language.
- Ratings
- Two screens for each description, each showing it: how much it applies to the participant, and how much it applies to the average person their age, from 1 (not at all) to 7 (very much) on seven buttons.
- Order
- Which question comes first is drawn from the session's seed and kept for every description, so half of the sessions start with each, or fixed by the study; the descriptions come in an order drawn from the seed. One practice description comes first and is not scored.
- Scores
- The blind spot: the average person's rating minus the participant's own over the 12 habits of thinking, from -6 to 6. Also the same difference over the 4 shortcomings and the blind spot beyond it, the mean ratings for oneself and for the average person, and the share of habits seen more in others.
Pronin, Lin and Ross (2002) compared biases with personal shortcomings, and Scopelliti and colleagues (2015) scored the average American's rating minus one's own on a scale from 1 to 7. This task uses that form with the average person of the participant's age and descriptions of its own, none of them an item of either source. Scores describe ratings of oneself beside the average person and are best compared between groups; they do not show how biased a person is and do not diagnose.
Quality checks
Each session is marked valid, needs review or invalid, with the reason, before you see its scores.
Scored rows: the scored run's ratings of the descriptions. No rating is correct, so accuracy is not judged against chance. A run with no habit of thinking rated for both the participant and the average person, or with fewer than half the descriptions rated for both, is invalid, and any other shortfall is flagged; one number chosen for at least 90% of the ratings is flagged. Ratings under 200 ms on at least half the screens invalidate.
Why these rules
There is no correct option to compare with chance, so accuracy is not judged against chance. The scores describe how much a person sees common habits of thinking in themselves beside the average person their age, so any rating is a possible answer, and so is rating both the same. The blind spot needs each description rated for both. One number for nearly every rating suggests the scale was not used; it is flagged for review because it can also be a real answer. An answer under 200 ms is faster than a simple visual reaction, so it cannot reflect the item. Following response-time effort screening for untimed tests (Wise and Kong 2005), the session is invalid only when at least half the answers are that fast.
No percentile. Scores and quality flags only.
Running this test
Settings you can change
| Setting | Standard | Allowed |
|---|---|---|
| Rated first | Drawn for each session (standard) | Drawn for each session (standard), The participant, The average person their age |
Yearly plans can change settings within these limits. Free and pay-as-you-go studies use the standard settings.
Need a setting this test does not have?
Devices and languages
- Untimed test: runs on desktops, laptops, tablets and phones. Participant devices
- Languages: English, Spanish, French, German, Italian, Portuguese (Brazil), Chinese (Simplified) and Japanese.
- Available on: Every plan, including the free plan.
- No percentile. Scores and quality flags only. How norms work
- Recruiting online? See the setup guides for Prolific, Sona Systems, CloudResearch Connect and Qualtrics.
Cite and describe
Participants completed the Bias Blind Spot Task in a web browser (ConductCognition task version 1.0.0, scoring version 1.0.0; Pronin E, Lin DY, Ross L, 2002; Scopelliti I, Morewedge CK, McCormick E, Min HL, Lebrecht S, Kassam KS, 2015), with the standard settings (rated first: Drawn for each session). The main score was blind spot (over the habits of thinking rated for both, the average person's rating minus the participant's own, from -6 to 6).
ConductCognition versions: task version 1.0.0, scoring version 1.0.0. Every export records the versions each session used, for a methods section.
- Pronin, E., Lin, D. Y., & Ross, L. (2002). The bias blind spot: Perceptions of bias in self versus others. Personality and Social Psychology Bulletin, 28(3), 369-381. https://doi.org/10.1177/0146167202286008
- Scopelliti, I., Morewedge, C. K., McCormick, E., Min, H. L., Lebrecht, S., & Kassam, K. S. (2015). Bias blind spot: Structure, measurement, and consequences. Management Science, 61(10), 2468-2486. https://doi.org/10.1287/mnsc.2014.2096The scale's form and scoring; this task uses none of its items.
- Chandrashekar, S. P., Yeung, S. K., Yau, K. C., et al. (2021). Agency and self-other asymmetries in perceived bias and shortcomings: Replications of the bias blind spot and link to free will beliefs. Judgment and Decision Making, 16(6), 1392-1412. https://doi.org/10.1017/S1930297500008470Three replications of Pronin and colleagues with 969 participants.
- West, R. F., Meserve, R. J., & Stanovich, K. E. (2012). Cognitive sophistication does not attenuate the bias blind spot. Journal of Personality and Social Psychology, 103(3), 506-519. https://doi.org/10.1037/a0028857Blind spots for classic cognitive biases, not smaller with higher cognitive ability.
Source papers
- Scopelliti and colleagues (2015): across five samples of 661 adults in the United States, recruited online, the mean blind spot on their 14-item scale from 1 to 7 was 1.48 (SD 0.95), and 85.2% showed a significant blind spot.Paradigm source, Adults
Questions
How long does the Bias Blind Spot Task take?
About 5 to 7 minutes, as listed in the test library.
What device does a participant need?
Untimed test: runs on desktops, laptops, tablets and phones. The browser must be Chrome, Edge, Firefox or Safari.
What scores does it produce?
Blind Spot, Gap on Shortcomings, Blind Spot Beyond Shortcomings, Own Rating of the Habits, Average Person's Rating of the Habits, Habits Seen More in Others, Median Rating Time, Ratings Under 100 ms and Descriptions Rated for Both. Each session is also marked valid, needs review or invalid, with the reason.
How widely is the Bias Blind Spot Task used in research?
89 papers from 2021 to 2025 name it in their title or abstract, up 75% compared with 2016 to 2020. That ranks it 276 of 632 test families in the ConductCognition test census (use grade D). Source: ConductCognition test census 0.44.0, counted 12 November 2026 from OpenAlex and ClinicalTrials.gov.
How much reliability evidence does the Bias Blind Spot Task have?
In the published research, 1 paper reports its test-retest reliability and 0 registered clinical studies use it as an outcome (evidence grade D in the ConductCognition test census).
Does it report a percentile?
No. Scores and quality flags only.
Which settings can a researcher change?
Rated first (Drawn for each session (standard), The participant, The average person their age). Settings can be changed on yearly plans; free and pay-as-you-go studies use the standard settings.
Which languages can participants use?
Participants can take this test in English, Spanish, French, German, Italian, Portuguese (Brazil), Chinese (Simplified) and Japanese, with its words in the same language. English is on every plan, and the other languages come with yearly plans. Have a native speaker read the machine-translated text before launch.
Is this a clinical test?
No. ConductCognition is for research use only. It runs, scores and exports the test; clinical interpretation is outside the platform.
Every test: the full test list.
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