Abstract
We describe our system for SemEval-2026
Task 10, Subtask 1: Conspiracy Marker Extraction (Samory et al., 2026), which involves
identifying spans of five marker types (Actor,
Action, Effect, Evidence, and Victim) in English social media text. Standard token-level
classifiers predict each position independently,
which can cause span fragmentation and ignores inter-marker dependencies. We present
a Span-Consistency Network (SCN) built on
DeBERTa-v3-large designed to address these
issues. First, a Span Consistency Layer (SCL)
propagates span-level signals to constituent tokens via a min-over-span, max-over-position
mechanism. Second, Cross-Marker Attention
(CMA) models co-occurrence patterns between
marker types through a learned correlation matrix. Third, we adopt a recall-biased Tversky loss augmented with Span Count Regularization (SCR), which penalizes mismatches
between predicted and gold span counts, penalizing diffuse probability distributions in favor of discrete spans. We ensemble five models trained via stratified cross-validation with
probability averaging. Our system achieved
a Macro F1 of 0.24 on the test set, placing
second among participating teams. Ablation
experiments on the development set show that
SCR has a large effect: its removal leads to prediction collapse for three of five marker types,
and that the Tversky loss outperforms binary
cross-entropy. We additionally provide a latency analysis of CMA, an analysis of how
SCL handles cross-type overlapping spans, and
an ablation on SCR warm-up scheduling.