MAS-I: Keep an assumption-first error log
A calculator error and an incorrect model assumption need different repairs. For each practice mistake, record the intended random variable, assumptions, setup and numerical calculation. This makes repeated conceptual errors visible instead of hiding them in an overall score.
Worked example or practice scenario
A Poisson-model mistake could be recorded as “used annual rate on a monthly interval.” A likelihood mistake could be “treated right censoring as an event.” A GLM mistake could be “interpreted log-link coefficient as an additive response change.”
Try this next
Create a fresh example for each error and solve it after a delay. Practise the current official item types in the official testing resources. Vendor difficulty levels and forum pass estimates are not substitutes for the content outline.
Reading sources
ActNet editorial guide · October 1, 2026 · Original illustrative examples.