Cited by 72Sentiment Analysis and Opinion MiningTopic ModelingEthics and Social Impacts of AI

Can we trust the evaluation on ChatGPT?

Open access
Aiyappa, Rachith, An, Jisun, Kwak, Haewoon, Ahn, Yong-yeol·2023·Proceedings of the 3rd Workshop on Trustworthy Natural Language Processing (TrustNLP 2023)

Abstract

ChatGPT, the first large language model with mass adoption, has demonstrated remarkable performance in numerous natural language tasks.Despite its evident usefulness, evaluating ChatGPT's performance in diverse problem domains remains challenging due to the closed nature of the model and its continuous updates via Reinforcement Learning from Human Feedback (RLHF).We highlight the issue of data contamination in ChatGPT evaluations, with a case study in stance detection.We discuss the challenge of preventing data contamination and ensuring fair model evaluation in the age of closed and continuously trained models.

AI snapshot

Written from the paper’s full text.

TL;DR

The paper argues that ChatGPT evaluations may be unreliable because the closed, continuously RLHF-updated model could be contaminated with evaluation datasets. In a stance-detection case study, newer ChatGPT versions showed improved zero-shot scores over an earlier version, but the authors cannot prove or rule out data leakage.

Key findings

  • On SemEval 2016 Task 6, Jan 30 ChatGPT improved over V1 by an average of 12.46 micro-F and 8.6 macro-F points; Feb 13 ChatGPT plus improved over V1 by 6.1 micro-F and 1.89 macro-F points.
  • On P-Stance, Feb 13 ChatGPT plus improved over V1 by 0.74 micro-F and 0.26 macro-F points.
  • On SemEval, performance dropped from Jan 30 ChatGPT to Feb 13 ChatGPT plus but remained above V1.
  • The authors argue that because ChatGPT is closed and continuously updated via RLHF, it is impossible to verify whether evaluation datasets were leaked; even input-only exposure can improve task performance.

Methods

  • Case study on stance detection using the test sets of SemEval 2016 Task 6 and P-Stance, with the same prompt as Zhang et al. (2022).
  • Collected Jan 30 ChatGPT responses manually for 860 SemEval tweets for targets Hillary Clinton, Feminist Movement, and Legalization of Abortion; later used an open-source API for Feb 13 ChatGPT plus on both P-Stance (2,157 tweets) and SemEval, manually extracting stance labels.
  • Compared zero-shot micro-F and macro-F scores across ChatGPT versions and against V1 results from Zhang et al. (2022).

Limitations

  • Stated: the analysis is illustrative; manual collection/extraction for Jan 30 SemEval was constrained by rate limits (approx. 40 queries/hour), variable response verbosity, and possible context accumulation from using a single chat session per sitting; Feb 13 used a new session per query; the authors could not repeat queries or estimate uncertainty; most critically, the results cannot prove or disprove data leakage or its effect.
  • Stated/evident: alternative explanations include the model simply getting better, catastrophic forgetting, or Feb 13 being more diplomatic; there are also uncertainties in Zhang et al. (2022) scores and prompt format, and only a few data points are available.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.18653/v1/2023.trustnlp-1.5

Cites

Statistics

Nothing to recompute.

Claims the paper makes

0 of 15 cited sources checked · 0 supported · 0 flagged

  • Findingown data

    Overall, we see an improvement in performance, measured using micro-F and macro-F scores, in recent versions of ChatGPT compared to V1.

    “Overall, we see an improvement in performance, measured using the micro-F and macro-F scores, in recent versions of ChatGPT compared to V1.”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: Zhang et al., 2022 used either the November 30 or December 15 version of ChatGPT (V1) to obtain their results.
    • The authors state this as an assumption: In Zhang et al., 2022, F1m is the micro average and F1-avg is the macro average.
  • Findingnone given

    The improvement is greater for SemEval than for the P-Stance dataset.

    “In sum, the improvement is greater for SemEval than for the P-Stance dataset.”
    Quote in the paperNot a substantial claim
    • The authors state this as an assumption: Zhang et al., 2022 used either the November 30 or December 15 version of ChatGPT (V1) to obtain their results.
    • The authors state this as an assumption: In Zhang et al., 2022, F1m is the micro average and F1-avg is the macro average.
  • Findingnone given

    On the SemEval dataset, we observe a performance drop by Feb 13 ChatGPT plus relative to Jan 30 ChatGPT.

    “On the SemEval dataset, we also observe a performance drop by Feb 13 ChatGPT plus relative to Jan 30 ChatGPT.”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: Zhang et al., 2022 used either the November 30 or December 15 version of ChatGPT (V1) to obtain their results.
    • The authors state this as an assumption: In Zhang et al., 2022, F1m is the micro average and F1-avg is the macro average.
  • Findingown data

    We see a significant jump in the zero-shot capability of ChatGPT when compared to previous models.

    “Although it is still difficult to conclude with only a few data points, we see a significant jump in the zero-shot capability of ChatGPT when compared to previous models.”
    Quote in the paperSubstantial claim
  • Findingown data

    There is an average of 12.46 and 8.6 point improvement in the micro and macro-F scores, respectively, when comparing Jan 30 ChatGPT to V1 on the SemEval task.

    “In particular, we see an average of 12.46 and 8.6 point improvement in the micro and macro-F scores, respectively, when comparing Jan 30 ChatGPT to V1 on the SemEval task.”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: Zhang et al., 2022 used either the November 30 or December 15 version of ChatGPT (V1) to obtain their results.
    • The authors state this as an assumption: In Zhang et al., 2022, F1m is the micro average and F1-avg is the macro average.
  • May combine two claims. 12
  • Classified as probably not a substantial claim. 14
  • May combine two claims.

    Findingown data

    On the P-Stance dataset, we observe a 0.74-point improvement in the micro-F scores and a 0.26 point in the macro-F scores when comparing Feb 13 ChatGPT plus to V1.

    “On the P-Stance dataset, we observe a 0.74-point improvement in the micro-F scores and a 0.26 point in the macro-F scores when comparing Feb 13 ChatGPT plus to V1.”
    Quote in the paperNot a substantial claim
    • The authors state this as an assumption: Zhang et al., 2022 used either the November 30 or December 15 version of ChatGPT (V1) to obtain their results.
    • The authors state this as an assumption: In Zhang et al., 2022, F1m is the micro average and F1-avg is the macro average.
  • May combine two claims.

    Findingown data

    There is a 6.1 point improvement on the micro-F and 1.89 point improvement on the macro-F when comparing Feb 13 ChatGPT plus to V1 on the SemEval task.

    “We see a smaller but nonnegligible improvement-6.1 point on the micro-F and 1.89 point on the macro-F-when comparing Feb 13 ChatGPT plus to V1 on the same task.”
    Quote in the paperNot a substantial claim
    • The authors state this as an assumption: Zhang et al., 2022 used either the November 30 or December 15 version of ChatGPT (V1) to obtain their results.
    • The authors state this as an assumption: In Zhang et al., 2022, F1m is the micro average and F1-avg is the macro average.
  • May combine two claims.

    Findingnone given

    Even though the performance has dropped, it is still quite an improvement compared to V1.

    “Even though the performance has dropped, it is still quite an improvement compared to V1.”
    Quote in the paperNot a substantial claim
    • The authors state this as an assumption: Zhang et al., 2022 used either the November 30 or December 15 version of ChatGPT (V1) to obtain their results.
    • The authors state this as an assumption: In Zhang et al., 2022, F1m is the micro average and F1-avg is the macro average.
  • Classified as probably not a substantial claim.

    Interpretationreasoning

    We cannot exclude the possibility that ground-truth output answers/labels of NLP tasks were submitted to the platform and ChatGPT was trained with such data.

    “Although we do not have any documented evidence that the ground-truth output answers/labels of the NLP tasks were submitted to the platform and the ChatGPT model has been trained with such data, we cannot exclude such possibility either.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Premisecitation

    ChatGPT is constantly updated, partly based on human inputs from more than 100 million users via RLHF.

    “Given that the ChatGPT's training datasets are unknown and that ChatGPT is constantly updated, partly based on human inputs from more than 100 million users via Reinforcement Learning from Human Feedback (RLHF) (OpenAI, 2022), it is impossible to ascertain the lack of data leakage, especially for the datasets that have been on the internet.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites OpenAI, 2022

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    ChatGPT is a closed model without information about its training dataset and how it is currently being trained.

    “However, given that the ChatGPT is a closed model without information about its training dataset and how it is currently being trained, there is a large loxodonta mammal in the room: how can we know whether ChatGPT has not been contaminated with the evaluation datasets?”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites OpenAI, 2022

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S2 (checkable), S4 (based).

    Interpretationnone given

    It is impossible to rule out the possibility of contamination without the model owners' in-depth analysis.

    “Although it is not possible to definitely answer these questions, it is also impossible to rule out the possibility of contamination without the model owners' in-depth analysis.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

    Premisenone given

    OpenAI has been updating the model primarily to address the model's problematic behaviors by making it more restricted, which led to the observation, although largely anecdotal, that the model has become 'less impressive.'

    “However, we would also like to note that OpenAI has been updating the model primarily to address the model's problematic behaviors by making it more restricted, which led to the observation, although largely anecdotal, that the model has become 'less impressive.'”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S4 (based). May combine two claims.

    Study design and conductreasoning

    Due to the same reasons mentioned above, we could not try multiple queries for each input and could not estimate the uncertainty of the performance.

    “Due to the same reasons mentioned above, we could not try multiple queries for each input and could not estimate the uncertainty of the performance.”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim. May combine two claims.

    Study design and conductnone given

    We used an open-source API for experiments with Feb 13 ChatGPT plus, which opened a new chat session per query.

    “In contrast, we used an open-source API for our experiments with the Feb 13 ChatGPT plus version, which opened a new chat session per query.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationreasoning

    As long as the trend of closed models and continuous training loop continues, it will become more challenging to prevent data leakage and ensure fair evaluation of models.

    “As long as the trend of closed models and continuous training loop continues, it will become more challenging to prevent data leakage (training-test data contamination) and ensure fair evaluation of models.”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim. May combine two claims.

    Interpretationreasoning

    Although we cannot rule out the explanation that ChatGPT is simply superior to previous models, it is also impossible to rule out the possibility of data leakage.

    “Although we cannot rule out the explanation that the ChatGPT is simply superior to previous models, it is also impossible to rule out the possibility of data leakage.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationown data

    Given results showing that even benign contamination can lead to measurable differences, making claims about these models' zero-shot or few-shot inference capabilities require a more careful inspection of the training datasets of these models.

    “Given the results showing that even benign contamination can lead to measurable differences, making claims about these models' zero-shot or few-shot inference capabilities require a more careful inspection of the training datasets of these models.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationcitation

    This may be one explanation for the drop in performance between Jan 30 and Feb 13 observed in Table 1 but recent work showed this to have an insignificant effect, although on a different dataset.

    “This may be one explanation for the drop in performance between Jan 30 and Feb 13 observed in Table 1 but recent work showed this to have an insignificant effect, although on a different dataset (Kocoń et al., 2023).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Kocoń et al., 2023

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationnone given

    Newer versions of ChatGPT are more likely to be exposed to past queries to the platform.

    “newer versions of ChatGPT are more likely to be exposed to past queries to the platform”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductown data

    Due to rate limitations, the collection was not done in one sitting since Jan 30 ChatGPT did not entertain more than approx 40 queries in an hour.

    “However, due to the rate limitations, this was not done in one sitting since Jan 30 ChatGPT did not entertain more than a fixed (approx.40) queries in an hour.”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim.

    Study design and conductnone given

    In each sitting, a single chat session was used to feed multiple inputs, one at a time, to ChatGPT, which may have accumulated context for subsequent inputs.

    “Additionally, in each sitting, a single chat session was used to feed multiple inputs, one at a time, to ChatGPT 10 , which may have accumulated context for subsequent inputs.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationcitation

    Given that ChatGPT is based on InstructGPT3 in which some NLP dataset contamination was already documented, this raises further concerns if V1 too may have been contaminated.

    “Given that ChatGPT is based on InstructGPT3 in which some NLP dataset contamination was already documented (Brown et al., 2020), this raises further concerns if V1 too may have been contaminated.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Brown et al., 2020

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S1 (asserted).

    Premisecitation

    Recent studies have claimed that ChatGPT outperforms most previous models for stance detection on existing evaluation datasets such as SemEval 2016 Task6 and P-stance, even in a zero-shot setting.

    “Recent studies have claimed that ChatGPT outperforms most of the previous models proposed for this task (Zhang et al., 2022) on a few existing evaluation datasets, such as the SemEval 2016 Task6 dataset (Mohammad et al., 2016(Mohammad et al., , 2017) ) and P-stance (Li et al., 2021), even in a zero-shot setting where the model was not fine-tuned on the task-specific training data.”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Zhang et al., 2022

      Not checked in the free run.

    • cites Mohammad et al., 2016

      Not checked in the free run.

    • cites Li et al., 2021

      Not checked in the free run.

19 of 19
  • The authors state this as an assumption.

    Zhang et al., 2022 used either the November 30 or December 15 version of ChatGPT (V1) to obtain their results.

    “Given that Zhang et al., 2022 was released on arXiv on December 30, 2022, and ChatGPT was launched on November 30, 2022, we assume Zhang et al., 2022 used either the November 30 or December 15 version of ChatGPT (henceforth called V1) to obtain their results (Fig. 1).”
  • The authors state this as an assumption.

    In Zhang et al., 2022, F1m is the micro average and F1-avg is the macro average.

    “In our work, hoping to capture the worst case scenario, we assume F1m is the micro average and F1-avg is the macro average.”
  • The authors state this as an assumption.

    The input query format presented in the screenshot of Zhang et al., 2022 is what was used.

    “We assumed that the format presented in the screenshot is what was used and selected it for this work with the neutral option being present (absent) for SemEval (P-Stance).”
3 of 3

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • The evolving nature of publicly available LLMs presents challenges because identical prompts at different points in time can produce very different results and changes to model specifications can lead to fluctuations in performance, even across short periods of time.

    “Moreover, the evolving nature of publicly available LLMs presents further challenges because identical prompts at different points in time can produce very different results20 and changes to model specifications can lead to fluctuations in performance, even across short periods of time21.”

The citation lists haven’t been fetched yet

References 23 · Cited by 72

Research works printed but not linked: 5

  1. Emily M Bender, Timnit Gebru, Angelina McMillan- Major, and Shmargaret Shmitchell. 2021. On the dangers of stochastic parrots: Can language models be too big? In Proceedings of the 2021 ACM confer- ence on fairness, accountability, and transparency, pages 610-623.
  2. Tom Brown, Benjamin Mann, Nick Ryder, Melanie Subbiah, Jared D Kaplan, Prafulla Dhariwal, Arvind Neelakantan, Pranav Shyam, Girish Sastry, Amanda Askell, et al. 2020. Language models are few-shot learners. Advances in neural information processing systems, 33:1877-1901.
  3. Nicholas Carlini, Florian Tramer, Eric Wallace, Matthew Jagielski, Ariel Herbert-Voss, Katherine Lee, Adam Roberts, Tom B Brown, Dawn Song, Ul- far Erlingsson, et al. 2021. Extracting training data from large language models. In USENIX Security Symposium, volume 6.
  4. Dilek Küçük and Fazli Can. 2020. Stance detection: A survey. ACM Computing Surveys (CSUR), 53(1):1- 37.
  5. Alec Radford, Jeffrey Wu, Rewon Child, David Luan, Dario Amodei, Ilya Sutskever, et al. 2019. Language models are unsupervised multitask learners. OpenAI blog, 1(8):9.

Authors
Aiyappa, R., An, J., Kwak, H., & Ahn, Y.-Y.
Affiliations
Indiana University Bloomington (US)
Venue
Proceedings of the 3rd Workshop on Trustworthy Natural Language Processing (TrustNLP 2023)
Published
2023
Pages
47-54
OpenAlex
W4385734111
Cited by
72
References
23
Citations by year
2026: 3 · 2025: 31 · 2024: 22 · 2023: 16
FWCI
12.69
Type
conference paper
Language
en
Open access
Licence
cc-by
Locations
  • Workshop on Trustworthy Natural Language Processing (TrustNLP) (publishedVersion, cc-by)
  • arXiv (Cornell University) (submittedVersion)
  • arXiv (Cornell University)
Funders
  • Defense Advanced Research Projects Agency (HR001121C0168)
  • Indiana University Bloomington
Topics
  • Physical Sciences › Computer Science › Artificial Intelligence › Sentiment Analysis and Opinion Mining
  • Physical Sciences › Computer Science › Artificial Intelligence › Topic Modeling
  • Social Sciences › Safety Research › Ethics and Social Impacts of AI
Keywords
ChatGPT, large language models, model evaluation, contaminated data, stance detection, reinforcement learning from human feedback, continuous training, assessment fairness

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