Research project · Speech & dialogue

MultiPartyTurnBenchBenchmarking Floor Control in
Multi-Party Spoken Dialogue

Evaluating when full-duplex voice systems should enter, hold, and relinquish the conversational floor in multi-speaker dialogue.

University of Maryland, College Park, USA

Overview of end-of-turn and interruption detection with positive events, hard negatives and excluded floor claims
Figure 1. Two complementary evaluation tracks: End-of-Turn (EOT) distinguishes genuine floor relinquishment from temporary holds; Interruption (INT) distinguishes successful takeovers from backchannels and other non-floor-taking speech.

Abstract

Full-duplex speech systems must decide when to enter, hold, or relinquish the conversational floor, even as multiple speakers overlap or backchannel without taking it. Existing evaluations study dyadic turn-taking or end-to-end agent behavior, but lack a unified, controlled evaluation of genuine floor transitions against confusable non-events in multi-party settings.

We introduce MultiPartyTurnBench (MPTB), a benchmark of 240 synthetically generated, channel-separated conversations spanning two to five speakers and six interaction types. MPTB evaluates two complementary tasks: End-of-Turn (EOT) detection distinguishes genuine turn completion from temporary holds, while Interruption (INT) detection distinguishes successful floor takeovers from non-floor-taking speech.

Exact event-conditioned annotations enable causal evaluation using false-positive-constrained recall and signed latency. Across acoustic, semantic, and turn-projection baselines, we find a stark asymmetry: learned systems achieve 82.5–92.6% EOT recall at 4.3–11.8% false-positive rates, while INT detection suffers from missed takeovers or excessive false activations. This asymmetry extends to five full-duplex agents which achieve 86.1–95.8% balanced accuracy on turn entry, yet perform near chance (46.9–54.7%) on selective interruption handling.

240Conversations
2–5Speakers
6Interaction types
6.89 hSpoken audio
The benchmark

What does it mean to control the floor?

Speaking activity is not the same as floor ownership. MultiPartyTurnBench isolates the decisions that matter for naturally timed group conversation.

01 · END-OF-TURN

Did the current speaker yield?

A real turn ending should trigger a response. A brief mid-turn pause should not.

Positive: genuine floor relinquishment Hard negative: hold pause
02 · INTERRUPTION

Did someone successfully take over?

A successful floor takeover matters; a backchannel or non-content vocalization need not.

Positive: successful interruption Hard negatives: backchannels, non-content

Controlled conversational conditions

SPEAKERS2 / 3 / 4 / 5

Speaker-count-controlled evaluation

INTERACTION STYLESSix distinct regimes

Casual, task-oriented, instructional, collaborative, argumentative, narrative

EVENT LABELSTimestamped floor state

Channel-separated audio with canonical event logs

Methodology

From event scripts to reproducible audio

A discrete-event orchestrator resolves floor ownership and timing before synthesizing speech, allowing causal evaluation with exact ground-truth events.

Five stages: dialogue scripting, floor-state orchestration, speech synthesis, acoustic rendering, and channel assembly
Figure 2. The five-stage conversation generation pipeline produces synchronized speaker tracks and an exact event log, including overlaps, interruptions, and backchannels. View vector PDF ↗
1

Dialogue scripting

Generate event-tagged conversations conditioned on speaker count and interaction style.

2

Floor orchestration

Resolve speaker roles, floor transitions, timestamps, and overlap.

3

Speech synthesis

Render each speaker with a distinct voice from the synthesis inventory.

4

Acoustic rendering

Add controlled ambient noise and nuisance events to synchronized tracks.

5

Release artifacts

Produce channel-separated audio, scripts, event logs, and metadata.

Causal event evaluation

Models predict EOT and INT events from audio observed up to the decision time. Positive events are matched to predictions within −0.25 s to +3.0 s; false activations are counted over event-specific hard-negative spans. Model thresholds are selected on the development split under a 10% FPR budget, then frozen for evaluation on the test split.

Evaluation matching windows, false positive span scoring, and development threshold selection
Figure 3. Event matching, negative-span scoring, and fixed-threshold testing. View vector PDF ↗
Results

Knowing when to speak ≠ knowing when to stop.

Across 12 offline baselines and five full-duplex agents, selectively recognizing floor takeovers is consistently harder than identifying turn endings.

KEY FINDING

End-of-turn is comparatively tractable. Selective interruption handling remains unresolved. The best FPR-qualified offline EOT result reaches 92.6% recall, but the best FPR-qualified INT result reaches only 56.2%.

Offline detection: EOT vs. INT

The same model can be reliable at detecting turn completion yet miss a large fraction of successful interruptions. The comparison below uses the development-selected thresholds reported in the paper; FPR and median latency are provided for context.

SystemEOT recallEOT FPRINT recallINT FPR
VAP92.6%7.5%11.7%2.8%
Kyutai SVAD92.5%4.3%56.2%6.6%
MuVAP88.1%10.2%34.5%8.6%
DualTurn89.4%10.8%37.0%8.2%
Mimi Endpointer90.5%3.8%13.9%3.8%

Selected models from Table 3. All rows satisfy the paper’s test FPR ≤ 15% qualification criterion. Complete results for 12 offline systems, including acoustic baselines and latency, are in the paper.

Full-duplex agents: the START / STOP gap

Balanced accuracy (%) START: enter floor STOP: yield selectively

Interactive agent evaluations from Table 4, across 120 scenarios repeated three times per system. START tests turn endings against holds; STOP tests genuine interruptions against backchannels. Dashed reference indicates 50% chance balanced accuracy.

OVER-YIELDING

97.7%

Gemini-3.8-Live yields to backchannels nearly indiscriminately, despite 100% yield recall on genuine interruptions.

UNDER-YIELDING

1.4%

MiniCPM-o-4.5 yields to only 1.4% of genuine interruptions—the opposite failure mode.

Why speaker count and interaction type matter

EOT recall is broadly stable from two to five speakers for several detectors, but interruption trends vary considerably by model. At five speakers, no plotted detector in the paper reaches 50% INT recall. Conversational style also matters: Kyutai SVAD ranges from 47.0% INT recall in collaborative dialogue to 77.5% in instructional dialogue.

Explore the benchmark, evaluate your own systems, and inspect the released conversation annotations.

Explore the dataset
Reference

BibTeX Citation

If you find MultiPartyTurnBench useful, please cite the paper.

@misc{mathur2026multipartyturnbench,
  title={MultiPartyTurnBench: Benchmarking Floor Control in Multi-Party Spoken Dialogue},
  author={Puneet Mathur and Dinesh Manocha},
  year={2026},
  eprint={2610.20172},
  archivePrefix={arXiv},
  primaryClass={cs.SD},
  url={https://arxiv.org/abs/2610.20172}
}