When modeling responses to items measuring non-cognitive constructs that require introspection (e.g., personality, attitude), most studies have assumed that respondents follow the same item response process—either a dominance or an unfolding one. Nevertheless, the results are not equivocal, as some preliminary evidence suggests that some people use an unfolding response process, whereas others use a dominance response process. To enhance item response modeling, it is critical to develop measurement models that can accommodate heterogeneity in the item response processes. Therefore, we proposed the Mixture Dominance-Unfolding Model (MixDUM) to formally identify this potential population heterogeneity. Monte Carlo simulations showed that MixDUM possessed reasonably good statistical properties. Moreover, ignoring item response process heterogeneity was detrimental to item parameter estimation and led to less accurate selection outcomes. An empirical study was conducted in which respondents completed focal personality scales under either an honest condition or a simulated job application condition, to demonstrate the utility of MixDUM. The findings indicated (1) that MixDUM provided the best fit across scales, (2) that approximately 55–60% of respondents utilized an unfolding response process, (3) that respondents exhibited moderate consistency in their use of response processes across scales, (4) that narcissism consistently negatively predicted the use of an unfolding response process, and (5) that the criterion-related validity of focal personality scores varied across latent classes for certain criteria. To encourage its use, we provided a tutorial on the implementation of MixDUM in the R package mirt.

中文翻译：

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一种方法并不适用于所有情况：使用混合优势展开模型 (MixDUM) 揭示项目响应过程的异质性


当对测量需要内省的非认知结构（例如个性、态度）的项目的反应进行建模时，大多数研究都假设受访者遵循相同的项目反应过程——要么是主导性的，要么是展开性的。然而，结果并不含糊，因为一些初步证据表明，有些人使用展开反应过程，而另一些人则使用主导反应过程。为了增强项目响应建模，开发能够适应项目响应过程中的异质性的测量模型至关重要。因此，我们提出了混合优势展开模型（MixDUM）来正式识别这种潜在的群体异质性。蒙特卡洛模拟表明 MixDUM 具有相当好的统计特性。此外，忽略项目响应过程的异质性不利于项目参数估计，并导致选择结果不太准确。我们进行了一项实证研究，受访者在诚实的条件下或模拟的工作申请条件下完成了焦点人格量表，以证明 MixDUM 的实用性。研究结果表明 (1) MixDUM 提供了跨尺度的最佳拟合，(2) 大约 55-60% 的受访者使用了展开的响应过程，(3) 受访者在跨尺度的响应过程的使用中表现出了中等程度的一致性，( 4）自恋始终负面地预测了展开反应过程的使用，以及（5）焦点人格得分的标准相关有效性在某些标准的潜在类别中有所不同。为了鼓励其使用，我们提供了有关在 R 包 mirt 中实现 MixDUM 的教程。