
🧠 Why guessing matters
Guessing on closed-ended knowledge items is common. Under likely-to-hold assumptions, the most common estimator of learning—the simple difference between pre- and post-process scores—is negatively biased when guessing occurs.
🔍 A latent-class fix that separates guessing from learning
🧪 Simulation evidence across many item and process types
A Monte Carlo simulation over a broad range of informative processes and knowledge items finds:
📣 Real-world test with Deliberative Polls
Applied to Deliberative Polls data, estimates of learning adjusted for guessing are about 13% higher than unadjusted difference scores. Accounting for guessing also eliminates the measured gender gap in learning and halves the pre-deliberation gender gap in political knowledge.
⚖️ Why it matters
Failing to adjust for guessing systematically underestimates learning and can create or exaggerate group disparities. The latent class approach offers a practical correction with a straightforward identifying assumption, improving the accuracy of learning measurement on closed-ended items.

| Guessing and Forgetting: A Latent Class Model for Measuring Learning was authored by Ken Cor and Gaurav Sood. It was published by Cambridge in Pol. An. in 2016. |