Abstract Filler particles (FPs) are used as indicators of fluency in second language (L2) speech research, yet their diverse phonetic exponents and their multifunctionality pose significant methodological challenges. This study critically examines the operationalization and measurement of FPs within the domain of utterance fluency. In order to better capture the multifaceted role of FPs, the domain of filler fluency is proposed alongside established categories such as speed, breakdown, and repair fluency. This study employs both static and dynamic approaches to critically evaluate FP measures in spontaneous, task-based L1–L2 dialogues involving 24 speakers. Static analyses show how the definition of FPs and how they are annotated affects the outcome of FP measurements. The dynamic, time-series methods explored here incorporate section-wise analyses, cumulative FP frequency trajectories, and sliding window techniques to capture intra-individual variability in FP use, revealing patterns that static averages often overlook.
Malte Belz (Mon,) studied this question.