Question 1

In item response theory models, the underlying latent trait is commonly referred to as ___________.

Accepted Answer

Theta is commonly used in item response theory models to represent the underlying latent trait that the test is designed to measure.

Question 2

The relationship between the underlying latent trait and the probability of answering an item correctly is called an _____________.

Accepted Answer

The correct term is "Item Response Function." It describes how the probability of a correct response to an item varies with the underlying latent trait that the item is intended to measure.

Question 3

Which of the following is not one of three parameters in the 3PL?

Accepted Answer

The 3PL (Three-Parameter Logistic) model in item response theory includes three parameters: discrimination, difficulty, and guessing. Reflection is not a parameter in this model.

Question 4

After a model has been estimated on your particular data set, which of the following would you examine to see how to specifically improve model-data fit?

Accepted Answer

Model modification indexes provide information on how the fit of the model could be improved by suggesting potential modifications, such as adding or removing paths or parameters.

Question 5

One strength of item response theory compared to classical test theory is that IRT statistics estimated from one population can be compared to statistics collected from a different population. This property is called _________.

Accepted Answer

Parameter invariance is a fundamental property of item response theory (IRT) that allows for the comparison of test statistics across different populations, as the item parameters are assumed to be the same regardless of the sample from which they were estimated.

Question 6

In confirmatory factor analysis, what is the preferred term by Shultz, Whitney, and Zickar (2021) for the item variance not explained by latent factors?

Accepted Answer

Shultz, Whitney, and Zickar (2021) prefer the term "residual" for the item variance not explained by latent factors in confirmatory factor analysis, as it accurately describes the variance in observed variables that is not accounted for by the model.

Question 7

In classical test theory, the concept of reliability is used to quantify measurement precision. In IRT, the analogous concept is called _________.

Accepted Answer

In Item Response Theory (IRT), the concept analogous to reliability in classical test theory is referred to as "information." Specifically, it's about how much information an item or a test provides about the underlying trait (e.g., ability) being measured.

Question 8

What is a minimum suggested sample size required to do most IRT analyses as suggested by Shultz, Whitney, and Zickar (2021)?

Accepted Answer

Shultz, Whitney, and Zickar (2021) suggest a minimum sample size of 250 for most IRT analyses to ensure adequate power and precision in parameter estimation.

Question 9

The idea that items should be uncorrelated with each other after controlling for the latent trait of the model is called ________.

Accepted Answer

Local independence is the concept that, within the framework of a latent trait model, the responses to individual items are uncorrelated with each other once the effect of the latent trait is accounted for. This means that after controlling for the latent trait, the response to one item does not predict the response to another item.

Question 10

Which of the following parameters is part of the 3PL model but not the 2PL model?

Accepted Answer

The 3PL (Three-Parameter Logistic) model includes guessing as a parameter, which is not part of the 2PL (Two-Parameter Logistic) model. The 2PL model includes difficulty and discrimination but not guessing or randomization.

Question 11

What are some key differences between classical test theory and item response theory.

Accepted Answer

The answer of What are some key differences between classical...

Question 12

What are assumptions and requirements that need to be met to use IRT?

Accepted Answer

The answer of What are assumptions and requirements that need...

Question 13

Which is better? Classical test theory or IRT?

Accepted Answer

The answer of Which is better? Classical test theory or...

Question 14

How can you decide what is the best IRT model for a particular data set?

Accepted Answer

The answer of How can you decide what is the...

Question 15

Describe the concept of item parameter invariance.

Accepted Answer

The answer of Describe the concept of item parameter invariance....

Quiz 20: Item Response Theory