VALIDATION

How has Lectora been validated?

Lectora has not been validated in a single one-shot study. It has been built with three academic partners over several years, and every partnership re-runs the same comparison against that course's own teacher's prior grading. The published anchor is a set of long-form written exams at the Faculty of Medicine at the University of Bergen, run blind against scores the examiners had already given. On them, Lectora's draft agreed with the course teacher at R² = 0.85, a stronger fitted linear relationship than the R² = 0.64 reported between two human graders on the same material. The question every partnership asks is the same one: is the draft close enough to review, or are you starting from scratch?

How closely does Lectora agree with the course teacher?

On long-form written exams at the Faculty of Medicine at the University of Bergen, Lectora's draft agreed with the course teacher at R² = 0.85. The two independent human graders who had already scored the same papers agreed with each other at R² = 0.64. Lectora was run blind, against the same rubric, with no access to either grader's scores.

Where two graders typically land0.50.60.70.80.91.0R² = 0.64Two human graders, same examR² = 0.85Lectora vs. course teacherAGREEMENT (R²) — FURTHER RIGHT IS CLOSER TO THE TEACHER

Lectora (0–100) ↑

Course teacher (0–100) →

Lectora vs. course teacher
R² = 0.85
Two human graders
R² = 0.64

Long-form written medical exams, University of Bergen · scored blind

Dots are illustrative.

How does targeted manual scoring keep the examiner in the loop?

Agreement matters because it decides where an examiner's time goes. In targeted manual scoring, examiners first score a small sample without seeing Lectora's drafts, which calibrates the drafts to their marking standard for that exam. Every submission whose pass/fail outcome is in doubt is then scored in full, examiners review the remaining drafts, and a qualified examiner approves every grade.

In a retrospective simulation on earlier exams, this allocation needed about 70% fewer manually scored tasks at one pass/fail boundary. That is a simulated task count, not minutes saved or a result for a letter-grade scale. The detailed calibration and selection rules are shared with participating institutions while the workflow is verified prospectively in pilots.

Full manual pass100%Targeted manual scoring30%−70%fewer manually scored tasksshare of tasks scored by handRETROSPECTIVE SIMULATION · ONE PASS/FAIL BOUNDARY · TASKS, NOT MINUTES

HUMAN IN THE LOOP · HOW THE SCORING WORK IS ALLOCATED

  1. Lectora

    Draft every submission

    Lectora drafts a score for each answer from the rubric and the examiner guidance.

  2. Examiners

    Calibrate on a human sample

    Examiners score a small sample without seeing the drafts, and Lectora's scores are aligned to their marking standard for this exam.

  3. Examiners

    Score the uncertain cases in full

    Every submission whose pass/fail outcome is in doubt goes to full manual scoring.

  4. Examiners

    Approve every grade

    Examiners review the remaining drafts, and a qualified examiner approves every grade before it is published.

In a retrospective simulation on earlier medical exams at the University of Bergen, this allocation needed about 70% fewer manually scored tasks at one pass/fail boundary. These are task counts, not measured time.

Where does the evidence come from?

Three academic partnerships, each re-running the same validation against its own course teacher's prior grading, including the parts where AI underperformed.

In the two independent mathematics studies at the Department of Mathematics at the University of Bergen, score agreement held: R² = 0.68 against the professor and about 88% agreement on pass or fail. The feedback result split by study design. When students saw instructor, peer and AI feedback side by side, they read the AI feedback least and rated it significantly less useful. When each student received either human-plus-AI or human-only feedback without knowing which, no significant difference in usefulness was detected (p = 0.45); the case study states that this is not proof of equivalence. When students could see the source they preferred the human; when they could not see it, no difference was detected. The same researchers also found agreement between graders falling from ICC 0.87 to 0.61 with the early prototype, which is on the cards below rather than left out.

Published

Faculty of Medicine

University of Bergen

R² = 0.85

against the course teacher

The published anchor: long-form written exams, scored blind against the examiners' own rubric and compared with the scores they had already given.

Read the case study →
Independent study

Department of Mathematics

University of Bergen

R² = 0.68

score agreement with the professor, measured by UiB researchers

Not our measurement. The same researchers found AI assistance dropped inter-rater agreement from ICC 0.87 to 0.61 on the early prototype, reported here because it is part of the evidence. On feedback, students who could see the source preferred the human.

Read the full findings →
Pilot in progress

Finance

NHH, Norwegian School of Economics

—

Pass/fail screening on long-form analytical hand-ins. Per-cohort figures are not published yet — the per-pilot summary goes to the course coordinator.

Read the pilot scope →

Read the full methodology → — what R² measures in grading, how the human baseline was produced, and how targeted scoring keeps an examiner on every grade.

~248,500

QUESTIONS & CASES GRADED ACROSS DEPLOYMENTS

…and growing every week.

20+ courses

IN PRODUCTION AND VERIFIED

Across medicine, mathematics, finance and more.

~70% fewer

UIB MEDICINE · TARGETED MANUAL SCORING

manually scored tasks in a retrospective simulation at one pass/fail boundary. Every grade still needs examiner approval.

On long-form written exams at the Faculty of Medicine at the University of Bergen, Lectora agreed with the course teacher at R² = 0.85, run blind against the same rubric. That is score agreement on long-form written exams. For comparison, two independent human graders on the same material agreed at R² = 0.64. The fitted score relationship was stronger for Lectora versus the course teacher in this comparison; R² alone does not measure the size of individual score differences. The UiB Medicine case study explains the comparison. The same loop is in pilot at the Department of Mathematics at UiB and at NHH Finance.