Finding

palmer-huk-shadlen-2005.psychometric.subject.phs-ah

Palmer J, Huk AC, Shadlen MN. The effect of stimulus strength on the speed and accuracy of a perceptual decision. Journal of Vision, 2005, 5(5):376-404. · Human random-dot motion button reaction-time task · psychometric

Observed curve and fits

Joint-fit companions

Other findings jointly fit by the same model fits.

Fit diagnostics

Caveats on these fits (1 term)

Each tag below is attached to one or more candidate fits for this finding. The chip column in the table flags which row carries which tag.

aggregate DDM RT approximation
DDM likelihood uses aggregate chronometric constraints rather than a full trial-level response-time likelihood.
Variant AIC Δ AIC RMSE Caveats
sdt-2afc winner 283.1 0.0 0.0489 —
logistic-4param 289.3 6.2 0.0528 —
ddm-vanilla 295.6 12.5 0.0727
  • aggregate DDM RT approximation
Full diagnostics (logL · n · params · max abs error)
Variant logL n Free params Max |error| Predicted points
sdt-2afc -139.6 554 2 0.1165 11
logistic-4param -140.6 554 4 0.1313 11
ddm-vanilla -144.8 554 3 0.2054 11

Residuals

Fit parameters and provenance

sdt-2afc.palmer-huk-shadlen-2005.psychometric.subject.phs-ah

dirty fit

criterion=-0.243 · d_prime=0.226

Method
scipy.optimize.minimize
Commit
24fd416
Predicted points
11
BIC
291.8

Fitted with scipy.optimize.minimize via behavtaskatlas.model_fits.sdt-2afc; success=True; CONVERGENCE: RELATIVE REDUCTION OF F <= FACTR*EPSMCH

logistic-4param.palmer-huk-shadlen-2005.psychometric.subject.phs-ah

dirty fit

bias=-1.019 · lower_lapse=0.000 · slope=2.581 · upper_lapse=0.000

Method
scipy.optimize.minimize
Commit
24fd416
Predicted points
11
BIC
306.6

Fitted with scipy.optimize.minimize via behavtaskatlas.model_fits.logistic-4param; success=True; CONVERGENCE: NORM OF PROJECTED GRADIENT <= PGTOL

ddm-vanilla.palmer-huk-shadlen-2005.psychometric.subject.phs-ah

dirty fit

boundary=1.417 · drift_per_unit_evidence=0.271 · non_decision_time=0.357

Method
scipy.optimize.minimize
Commit
67b9019
Predicted points
11
BIC
308.5

Fitted with scipy.optimize.minimize via behavtaskatlas.model_fits.ddm-vanilla; success=True; CONVERGENCE: RELATIVE REDUCTION OF F <= FACTR*EPSMCH

Observed points

Signed motion coherence p_right n
-51.200 0.0000 46
-25.600 0.0000 48
-12.800 0.0000 45
-6.400 0.1277 47
-3.200 0.4318 44
0.000 0.4946 93
3.200 0.8750 48
6.400 0.9778 45
12.800 1.0000 45
25.600 1.0000 45
51.200 1.0000 48

Take it with you

Cover sheet

Self-contained Markdown for citation, slides, or notebooks

The cover sheet pins the finding to the atlas commit and includes the observed points, fit ranking, caveats, and provenance — everything needed to drop into a paper or notebook without losing the trail back to the deploy.