The second-order multidimensional IRT model for testlets is formally equivalent to the testlet model, and both are restricted bifactor models¶

Claim · All claims
Evidence · 1 study · theoretical r3 · q2
Currency · newest study 2009 · not yet checked against its sources · not reviewed by a person · overdue for a recheck since 2012: tool and model accuracy changes quickly

Subclaims¶

q2 i? Algebraic manipulation of the second-order model's equations shows it is formally equivalent to the testlet model, which itself is a bifactor model with proportionality restrictions within each testlet. → Rijmen 2009

Evidence¶

Rijmen 2009¶

Rijmen, F. (2009). Three Multidimensional Models for Testlet-Based Tests: Formal Relations and an Empirical Comparison. ETS Research Report RR-09-37. http://www.ets.org/research/contact.html doi:10.1002/j.2333-8504.2009.tb02194.x

q2 · i? · theoretical · r3

Analytical derivation comparing Equation 7 to the bifactor model's Equation 2 under standard normal latent variables. The derivation shows the second-order model is a restricted bifactor model with the same restrictions that yield the testlet model, and the article notes this equivalence had not been explicitly described before, to the knowledge of the author.

"some further algebraic manipulations of Equation 7 clearly show that the second-order model is formally equivalent to the testlet model"

Discussion¶

Related Claims¶

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