📄
Abstract - From Text to Parameters: Predicting Item Parameters from Embedding Regularization with Reliability and Design Ceilings
Newly developed items must ordinarily be field tested before their psychometric properties are known, creating a cold start problem for item calibration. Predicting item parameters from features is a long standing measurement problem dating back to the Linear Logistic Test Model; modern text embeddings now automate the design matrices traditionally specified by hand. We propose an evaluation framework combining regularized regression on item text embeddings, repeated cross validated R squared reported with its resampling standard deviation, and two performance upper bounds: a reliability ceiling derived from parameter standard errors, and a design ceiling derived from simulation based power calibration. Applying this framework to a mathematics item bank (EEDI) and a medical licensure benchmark (BEA 2024), we find that item difficulty is highly predictable from text (repeated cross validated R squared = 0.53, or about 57% of its reliability ceiling), whereas discrimination and pseudo guessing appear less predictable. However, evaluating these results against our ceilings reveals that this apparent hierarchy stems from target reliability rather than text signal strength: text uniformly recovers 57 to 63% of the reliable variance across difficulty targets, whereas the 3PL pseudo guessing parameter has a reliability ceiling near zero, making it an unviable target at current precision. On BEA, embedding based regression matches leaderboard RMSE despite explaining almost no variance, highlighting the critical need for scale free metrics and explicit ceilings in benchmarking. Finally, we show that a single train and test split can inflate apparent accuracy by 0.1 to 0.15 in R squared, underscoring the necessity of repeated cross validation for calibration support applications and future benchmark construction.
从文本到参数:基于嵌入正则化预测项目参数,兼论可靠性与设计上限 /
From Text to Parameters: Predicting Item Parameters from Embedding Regularization with Reliability and Design Ceilings
1️⃣ 一句话总结
本文提出了一种基于文本嵌入和正则化回归来预测考试题目难度等参数的方法,通过引入可靠性上限和设计上限来评估预测效果,发现题目难度可以从文本中可靠预测,而区分度和猜测参数预测效果较差,原因在于参数本身的可靠性低而非文本信息不足,并指出单次训练测试分割会夸大预测精度,强调了重复交叉验证的必要性。