Item Response Theory (IRT) Flashcards
6 cards from real TAPAS practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Item Response Theory (IRT) flashcards as text
What is maximum likelihood estimation as used in TAPAS scoring?
Answer: A statistical method that finds the trait values most consistent with the observed pattern of item responses
Maximum likelihood estimation finds the personality dimension scores that maximize the probability of observing the person's actual pattern of forced-choice responses, given the IRT model and item parameters.
What is Bayesian estimation and how might it be used in TAPAS scoring?
Answer: An estimation approach that combines prior information about typical trait distributions with the observed response data
Bayesian estimation incorporates prior knowledge about the population trait distribution along with the individual's response pattern to produce trait estimates, which can be particularly useful early in the adaptive test when few responses are available.
How does IRT enable equating of TAPAS scores across different item sets?
Answer: Because IRT parameters are on a common scale, scores from different item subsets are directly comparable regardless of which specific items were administered
IRT places all items and people on a common metric, meaning that trait estimates from different subsets of items are directly comparable, which is essential for CAT where everyone takes different items.
What is model-data fit and why is it assessed for TAPAS?
Answer: Statistical evaluation of how well the MUPP-IRT model describes the actual pattern of responses in the data
Model-data fit assesses whether the MUPP-IRT model adequately describes how people actually respond to TAPAS items, which is necessary for the model's parameters to yield accurate scores.
What is the theta parameter in IRT and what does it represent in TAPAS?
Answer: The estimated standing of a person on a latent personality dimension, typically scaled with mean 0 and standard deviation 1
Theta represents the person's estimated level on a personality dimension in the IRT metric, where 0 represents the average of the calibration population and positive/negative values indicate above/below average standing.
How does IRT handle missing data or interrupted TAPAS administrations?
Answer: IRT can estimate trait levels from any subset of items, so incomplete administrations still yield usable estimates with appropriately wider confidence intervals
Because IRT estimates traits from whatever items are available, an interrupted TAPAS session can still produce valid personality estimates, though with reduced precision reflected in larger standard errors.