📐
IRT Analyzer Pro
Item Response Theory · Psychometric Analytics
1PL · 2PL · 3PL
1
Step 1
Import
2
Step 2
Parameters
3
Step 3
Theta (θ)
4
Step 4
Scores
5
Step 5
Details
6
Step 6
ICC / IIF
📂
Import Response Data
Upload a CSV of student responses or load sample data to begin.
ℹ️
CSV format: first column = Student ID, remaining columns = item responses (1 = correct, 0 = wrong).
Optionally include rows labeled b, a, c for embedded item parameters.
Omitted answers: leave blank or use NA, ., or -. Omitted items are not counted as wrong.
📤
Click to upload or drag & drop CSV
Dichotomous (0/1) responses · Student ID in first column
📊
Item Parameters
Estimated IRT parameters for each test item.
📊
Import response data and run analysis to view item parameters.
θ
Theta (θ) Estimation
Latent ability estimates per student with standard errors.
θ
Complete the analysis to view theta estimates.
🎯
Score Conversion
Theta-to-score linear transformation and distribution.
🎯
Complete the analysis to view score conversions.
📋
Item Score Details
Item-level IRT scores and response breakdown per student.
📋
Complete the analysis to view item-level details.
📈
ICC & Item Information
Item Characteristic Curve and Item/Test Information Functions.
⚙️ Item Parameters
Derived Stats
P(θ=b)
Info @ b
Peak Info θ
🎯 Quick Item Selector
Run analysis to load items.
📈 Item Characteristic Curve (ICC)
🔋 Item Information Function (IIF)