Contributor
Medha Shekhar (bsmedha@gmail.com)

Citation
Shekhar, M. & Rahnev, D. (2021). The nature of metacognitive imperfection in perceptual decision making. Psychological Review, 128, 45-70. 

Stimulus
Gabor patches of 3 different contrasts embedded in noise. The Gabor patches were oriented at 45 degrees away from vertical. 1: left (counterclockwise) orientation, 2: right (clockwise) orientation.

Confidence scale
A continuous 50-100 scale. Subjects were required to report their estimated certainty from 50% (chance) to 100% (absolutely sure).

Manipulations
None. Three contrast levels were randomly interleaved.

Block size
50. Each subject came for 3 days. On Day 1, subjects completed 4 runs of 4 blocks each (800 trials). On Days 2 and 3, subjects completed 4 runs of 5 blocks each (1,000 trials/day).

Feedback
No feedback was given except during training.

Subject population
Young adults.

Response device
Computer mouse.

Training
5 blocks of training with feedback.

Experiment goal
Build a model of confidence generation.

Special instructions
None.

Experiment dates
Data were collected between October, 2017 and April, 2018.

Location of data collection: Rahnev lab at Georgia Tech, Atlanta, GA, USA.