Why two-person data is not enough

In a two-person conversation, when one person stops, the other is usually next. A model trained on pairs learns a simple rule: wait for the other side to finish, then speak. Most end-of-turn detection work is built on that setup, and the MP-Bench authors note that recent benchmarks mostly evaluate two-person interaction.

Add a third person and the rule fails in several ways:

Zhu, Miyoshi, and Okafuji give a concrete case: a person asks a robot for help while someone standing nearby comments casually on the store layout. A robot that answers every utterance it detects interrupts the people around it or answers the wrong person (Zhu et al., 2025). 1X describes the same goal for its NEO humanoid, which it says recognizes when it is being addressed and responds only when appropriate (The Robot Report).

Addressee and floor control

Two ideas carry most of the multi-party problem.

Both decisions need labels that two-person data does not have. Addressee labels need at least three people. Floor labels need to mark, for each overlap, whether the floor changed hands.

What the benchmarks show

Three benchmarks released in 2026 test these decisions directly.

BenchmarkWhat it testsDataFinding
MultiPartyTurnBenchEnd-of-turn and interruption detection with 2 to 5 speakers240 synthetic, channel-separated conversations in six interaction typesFive full-duplex agents scored 46.9% to 54.7% on selective interruption handling
MultiTalkBenchLong multi-party dialogue, including addressee selection104 real recordings, 60 English and 44 Chinese, averaging 32.6 minutesReleased with a model that beats Moshi, MiniCPM-o-4.5, and Qwen3-Omni on it
MP-BenchVoice agents as participants: turn-taking awareness and response appropriatenessMulti-party conversations with comprehension questions12 voice agents tested; real-time agents stay at or below 22% on comprehension and near chance on turn-taking

Sources: Mathur and Manocha, 2026; Wang et al., 2026 and the MultiTalkBench card; Shih et al., 2026.

MultiPartyTurnBench gives the sharpest picture. Learned end-of-turn detectors reached 82.5% to 92.6% recall at 4.3% to 11.8% false-positive rates, so end-of-turn detection holds up reasonably well even with five speakers. Interruption detection does not. The same five agents scored 86.1% to 95.8% balanced accuracy on entering a turn, then fell to near chance on deciding which overlaps to yield to. At the extremes, Gemini-3.8-Live yielded to 97.7% of backchannels, and MiniCPM-o-4.5 yielded to only 1.4% of genuine interruptions: one stops for almost every "mm-hm", and the other talks over people who are taking the floor.

Our reading of all three: current agents handle the end of a turn better than the overlaps inside it. They cannot yet tell a takeover from a backchannel or a side remark, and we think that is as much a training data problem as a model problem. The evaluation overview on fullduplex.ai covers how these metrics are computed.

Synthetic and real multi-party data

The MultiTalk authors write that open multi-party speech corpora remain small and are not designed for full-duplex modeling at the codec-frame level. Their answer was 57.6k hours of synthetic training dialogue with controllable participant count, overlap, backchannels, interruptions, and addressee shifts (Wang et al., 2026). MultiPartyTurnBench is synthetic too, built from scripted dialogue, synthesized voices, and timing statistics taken from AMI, and it checks its detectors against real two-person TurnBench audio and four-person AMI meetings (Mathur and Manocha, 2026).

Synthetic data gives coverage and exact labels. Its timing is generated, not observed, and MultiPartyTurnBench draws on a pool of 24 synthetic voices. Real recordings give the timing, prosody, and acoustics that a robot will meet in a room. We think a robot team needs both: synthetic dialogue to cover rare floor events at scale, and real group conversation to learn timing and to evaluate on. Robot-specific data is still tiny. The multi-party human-robot dataset Zhu and colleagues built, with a Sota robot and two people, runs to 82 minutes and 1,111 dialogues labeled with speaker and intended recipient.

Multi-party datasets you can use

DatasetPeople per sessionAudioSettingLicense
AMI4 in the scenario meetings, about two-thirds of the dataClose-talking and far-field microphones, plus video100 h of meetings in three roomsCC BY 4.0
ICSIGroup meetingsClose-talking microphones, as separate files or one mixAbout 70 h of meetingsCC BY 4.0
CHiME-64Binaural microphones on each person plus six 4-microphone arrays, 16 kHz20 dinner parties in homes, about 50 hCC BY-SA 4.0
Basis Conversations 15002 to 4One 48 kHz channel per speaker2,645 speakers, median 33 minutes per conversationCustom license, gated
MultiTalkPT / FTVariesSynthetic, with a speaker-to-channel mapEnglish and Chinese, 57.6k hCC BY-NC 4.0
otoSpeech Face-to-Face2 to 516 channels, 48 kHz, 24-bit, in one roomCasual and deliberative sessionsOn request
otoSpeech 3-Speaker3One 48 kHz mono file per speakerSpontaneous conversationOn request

Sources: AMI, ICSI, the CHiME-5 data page and OpenSLR 150, the Basis dataset card, the MultiTalkPT card, and oto's Face-to-Face and 3-Speaker pages.

The real recordings fall into two kinds, and a robot needs both:

What to ask for

Where oto fits

oto builds conversation data with each speaker on a separate channel, in English, Japanese, and Korean.

For the first-person side of the problem, see What Conversation Data Does a Humanoid Robot Need?

Data for voice AI

Request samples or a quote

Tell us what you are building, and we will send samples and pricing for the data that fits.

Frequently asked questions

What is multi-party conversation data?

Recordings of three or more people talking together, ideally with a separate channel for each speaker so overlapping speech can be attributed.

Why can't a robot learn group conversation from two-person data?

In pairs, the other person is almost always next. With three or more, the robot has to decide whether it is being addressed at all, and two-person data has no examples of that choice.

What is addressee detection?

Working out who an utterance is meant for, from words, names, gaze, and body orientation. Robots in groups need it to avoid answering speech meant for someone else.

Are there benchmarks for multi-party turn-taking?

Yes. MultiPartyTurnBench, MultiTalkBench, and MP-Bench were released in 2026. MultiPartyTurnBench and MP-Bench both find current voice agents weak at multi-party floor control.

Which datasets have multi-speaker conversation with separate channels?

AMI, ICSI, and CHiME-6 have close microphones in a shared room. Basis Conversations 1500 and otoSpeech 3-Speaker have a clean track per speaker, and otoSpeech Face-to-Face has 16 in-room channels with two to five people.

For more datasets, benchmarks, and models, see the fullduplex.ai catalog.

otoearth, Inc.