Digital-first assessments are delivered continuously and often remotely. Artificial intelligence (AI) enables digital assessments to generate content and administer tests at scale. Like any system used for high-stakes decision-making, digital assessments require responsible AI (RAI) practices to ensure fairness and validity. This paper presents two deployed systems in the Duolingo English Test (DET) lifecycle that align the DET to its RAI Standards. The Item Factory combines automated item generation with staged expert review; the Analytics for Quality Assurance in Test Taker (AQUA-TT) system applies unsupervised anomaly detection methods to continuously monitor for issues in digital test deliveries for daily individual test sessions. We present the design and performance of these systems and discuss what they imply for placing human judgment inside digital assessments.

Prior automated writing feedback systems have shown limited evidence of transferable writing development. This pilot longitudinal study examined whether repeated interaction with process-oriented LLM feedback improved independent writing performance over time. Results suggest positive transfer effects across novel writing tasks, supporting the potential developmental role of LLM-mediated feedback.

Estimating item parameters (e.g., the difficulty of a question) is an important part of modern high-stakes tests. Conventional methods require lengthy pilots to collect response data from a representative population of test-takers. The need for these pilots limit item bank size and how often those item banks can be refreshed, impacting test security, while increasing costs needed to support the test and taking up the test-taker’s valuable time. Our paper presents a novel explanatory item response theory (IRT) model, BERT-IRT, that has been used on the Duolingo English Test (DET), a high-stakes test of English, to reduce the length of pilots by a factor of 10. Our evaluation shows how the model uses BERT embeddings and engineered NLP features to accelerate item piloting without sacrificing criterion validity or reliability.

Neural methods for embedding entities are typically extrinsically evaluated on downstream tasks and, more recently, intrinsically using probing tasks. Downstream task-based comparisons are often difficult to interpret due to differences in task structure, while probing task evaluations often look at only a few attributes and models. We address both of these issues by evaluating a diverse set of eight neural entity embedding methods on a set of simple probing tasks, demonstrating which methods are able to remember words used to describe entities, learn type, relationship and factual information, and identify how frequently an entity is mentioned. We also compare these methods in a unified framework on two entity linking tasks and discuss how they generalize to different model architectures and datasets.