PaperHub
5.5
/10
Rejected4 位审稿人
最低2最高5标准差1.1
2
4
5
3
3.8
置信度
创新性3.3
质量2.8
清晰度3.3
重要性2.8
NeurIPS 2025

From Machine to Human Learning: Towards Warm-Starting Teacher Algorithms with Reinforcement Learning Agents

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提交: 2025-05-12更新: 2025-10-29
TL;DR

We use RL agents to warm-start AI teacher algorithms for personalized learning, reducing the need for extensive human learning data while achieving effective adaptive curricula for humans in game-based training environments.

摘要

关键词
AI for Human Learninggamified learning environmentsteacher algorithmsautomated curricula

评审与讨论

审稿意见
2

The authors present a RL approach to build curricula to train RL agents, a method for quantifying the transfer opportunities for tasks is contributed and the method learns how to perform optimal task sequencing to improve learning.

优缺点分析

Strengths:

  • The authors present a novel approach for an important problem that is still not completely solved
  • Paper is well-written and clear.

Weaknesses

  • The main (and fatal) weakness of the paper is that the authors seem to be completely unaware of a significant body of work in this area. To being with, the two main surveys in the area are not even mentioned, which by reading the authors would be exposed to many related workers that were not mentioned:

Silva, Felipe Leno, and Anna Helena Reali Costa. "A survey on transfer learning for multiagent reinforcement learning systems." Journal of Artificial Intelligence Research 64 (2019): 645-703.

Narvekar, Sanmit, et al. "Curriculum learning for reinforcement learning domains: A framework and survey." Journal of Machine Learning Research 21.181 (2020): 1-50.

Related to this, the experimental approach does not bring any other related approach to compare performance. Quoting from the manuscript: "The core innovation of SimMAC lies in its ability to identify knowledge overlap between tasks.", yet the authors completely ignored early curriculum papers that proposed transferability metrics that should be directly usable in the authors scenario:

Silva, Felipe Leno Da, and Anna Helena Reali Costa. "Object-oriented curriculum generation for reinforcement learning." Proceedings of the 17th international conference on autonomous agents and multiagent systems. 2018.

Svetlik, Maxwell, et al. "Automatic curriculum graph generation for reinforcement learning agents." Proceedings of the AAAI conference on artificial intelligence. Vol. 31. No. 1. 2017.

Finaly, both Mattisen and Sukhbaatar propose methods where constructing the sequence of actions is modeled as an RL problem, at least one of them could be easiy added to the experimental evaluation to compare the methods.

Matiisen, Tambet, et al. "Teacher–student curriculum learning." IEEE transactions on neural networks and learning systems 31.9 (2019): 3732-3740.

Sukhbaatar, Sainbayar, et al. "Intrinsic motivation and automatic curricula via asymmetric self-play." ICLR 2018

In Summary, the paper is promising but needs significant work to be put in the context of the other works in the area, and a number of baselines are missing in the experimental evaluation so we can't really be sure the results achieved are good.

问题

No Specific question that would make me change my rating.

局限性

yes

最终评判理由

By the end of the discussion with the other reviewers the summary of the main concerns is that 1) the task similarity metric is ad hoc and not grounded in human cognition research. 2) an RL-based approach for human modeling was not fully justified, and 3) lack of comparison with the literature in Curriculum Learning for RL.

For points 1) and 2) I think have a problem with it personally. It would be better if the task similarity was grounded in psychology literature but in the end of the day for both 1) and 2) what matters is that it works (with the caveat that there are similarly-motivated task similarity metrics in the literature that the authors seem to not have heard about, demonstrating poor knowledge of the literature).

as for 3) the authors responded that the original curriculum learning approaches did not focus on human learning and that they need "a lot of data". The statements are not wrong but completely inconsequential in the context that it was put in the review for the authors to respond. It indeed require "a lot" of data for that (I put it on quotes because it's nowhere close to the magnitude of that data we use to train llms nowadays, but a lot if we intend to gather from humans). However, in order to compare with the literature approaches the authors didn't have to gather data feom humans. They could simply build curricula using RL agents "pretending " to be humans ,which would lead to a curriculum and in case the author's hypothesis that their method works better for humans than the other works, the curriculum produced by them should be much better in the human evaluation than the "RL mock" curriculum.

I really have no confidence that the author's proposal is in any way better than any of the already-published works in producing human-focused curricula, tho they don't explicitly consider humans at all. In other words, does the work proposed really works well with humans or is it just better than having nothing and if we had provided a curriculum created for RL agents to the humans they would perform the same or better than with the proposal's curriculum?

IMO a paper that doesn't answer that question and shows complete unawareness of a large body of related work is not ready for Neurips

格式问题

N/A

作者回复

We appreciate the reviewer's engagement and would like to clarify our work's scope and contributions, which differ substantially from the cited literature.

Our Focus: RL-to-Human Transfer, Not RL-to-RL

Our work addresses a distinct problem: using RL agents to bootstrap teacher algorithms for human learners, not RL agent training. The reviewer's summary ("RL approach to train RL agents") mischaracterizes our contribution. We propose solving the cold-start problem in human education by using RL-generated synthetic data to warm-start teacher algorithms, then deploying these teachers with human subjects.

Why Existing RL Curriculum Literature Doesn't Apply

The cited works (Silva & Costa 2019, Narvekar et al. 2020, Matiisen et al. 2019, Sukhbaatar et al. 2018) focus on RL-to-RL transfer with fundamentally different constraints:

  • [Scale]: These methods require millions of timesteps across small number of tasks; our humans interact with only 10-17 episodes across 3000 timesteps
  • [Feedback]: RL curricula rely on value functions and dense rewards unavailable in human settings
  • [Applicability]: Self-play mechanisms (Sukhbaatar 2018) and evolutionary approaches (ACCEL) are impractical for human learners due to time and feasibility constraints.

Our Baselines Are Appropriate

We compare against standard human learning baselines (random, handcrafted, no-training controls) consistent with human subjects literature (Bassen et al. 2020, Doroudi et al. 2019: tables 3,4,5,6,7). In particular, owing to the interleaved practice effect (Taylor K, Rohrer D, 2010, Ebbinghaus 1948), random curricula are by no-means a trivial curricula for humans (Zhou et al, 2017, Shen et al 2018a). Indeed, most of the early prior works failed to show significant effects over a random curriculum (Doroudi et al 2019). Our contribution lies in demonstrating that RL-initialized curricula can match expert-designed sequences while requiring no domain expertise.

Novel Contribution

To our knowledge, we are the first to bridge RL synthetic data generation with human curriculum design, validated through controlled human subjects studies (n=471 across two domains).

We welcome incorporating the suggested references to better contextualize our work within the broader curriculum learning landscape.


Zhou, G., Wang, J., Lynch, C.F., Chi, M. (2017). Towards closing the loop: Bridging machine-induced pedagogical policies to learning theories. In Proceedings of the 10th international conference on educational data mining (pp. 112–119). International educational data mining society.

Shen, S., Ausin, M.S., Mostafavi, B., Chi, M. (2018a). Improving learning & reducing time: a constrained action-based reinforcement learning approach. In Proceedings of the 2018 conference on user modeling adaptation and personalization: ACM

Taylor, K., & Rohrer, D. (2010). The effects of interleaved practice. Applied Cognitive Psychology, 24(6), 837–848. https://doi.org/10.1002/acp.1598

Ebbinghaus, H. (1948). Concerning memory, 1885. In W. Dennis (Ed.), Readings in the history of psychology (pp. 304–313). Appleton-Century-Crofts. https://doi.org/10.1037/11304-034

评论

If I understand correctly the paper focuses on performing transfer to warm-start the teacher algorithm that IS a RL learner. Therefore, regardless of the particular application being using this RL method to teach humans it's still a RL training task, with the difference that you need to run the human trials to get a final performance measure.

Therefore, I stand by that the whole literature of Curriculum for RL applies and should have been considered for the empirical evaluation. Even if I can understand that the existing curricula-building techniques were not specialized having human learners in mind, that should not be a deterrent in using them to build a curriculum and showing in your experimental evaluation that they perform significantly worse in helping the humans to learn the task.

In special, any approach in the field should be possible to evaluate by using it to define what is the best curriculum for an "RL agent" and providing this curriculum as is to the humans.

评论

We thank the reviewer for his early reply, and would like to clear up misconceptions. In this work, we primarily focused on using RL agents to generate relevant data for our teacher algorithm. Our teacher algorithms are NOT trained by RL, but merely leverages data from RL agents to train on. For example, PERM-H collected (θ,r) tuples from observing an RL student training to achieve an Item-Response Theory model, which is trained by a variational objective.

In our work, we adopted the UPOMDP (Section 3) to draw links to RL and Human training to frame our discussion and drive similarities, but we do not use RL-like mechanisms to assume how humans train. We do not use reward functions during our human training to make any assumptions about human performance.

As we have asserted in the paper and in our rebuttal, all the prior work that focuses on curriculum learning for RL does not apply well to humans, especially on the inordinate amount of data required to train these algorithms in. While bearing in mind that we have 1 hour with our human subjects, aligning these algorithms to human-time scale trivializes these prior work:

  • ACCEL (Parker-Holder et al, 2022) uses value estimation functions, which are not available from humans, and evolutionary methods to discover new environments. Constraining the approach to 10 environments (which we use in our Jumper experiment) is akin to random initialization with an almost static curriculum.

  • TSCL (Matiisen et al 2017; proposed by reviewer) uses sampling methods that are based on observing performance on each task K times. In our case, K=1 for our tasks, and the algorithms will not be able to converge, leading to a curriculum that is akin to random sampling, which we have also included. Notably, TSCL algorithms (Figure 5) do not beat the manual curriculum on the 2D addition task, which we have already included in our paper.

  • Sukhbaatar et al (2018; proposed by reviewer) proposes self-play "show-and-reverse" as a curriculum which is a concept that is infeasible for humans. The best approximate implementation of Sukhbaatar et al's work for humans would be to get human students choose their own task, but one would easily argue that they are not equivalent given the sophistication behind the reward function expected of Alice and Bob.

While we could theoretically adapt these algorithms for human learning contexts, the examples above demonstrate that doing so would require such substantial modifications that the resulting approaches would no longer meaningfully represent the original methods. Any comparative evaluation would therefore be inherently unfair, as we would be comparing our approach against fundamentally altered versions of the baseline methods rather than their intended implementations.

We therefore firmly reject the reviewer's assertion that these works "could be easily added to the experimental evaluation". Such a characterization fails to acknowledge the significant constraints and assumptions involved in translating RL-based curriculum learning approaches to human subject studies.

We ask the reviewer to recognize that our work specifically addresses human learning within the practical constraints of limited time, data, and cost. These constraints necessitated the development of new methods rather than the adaptation of existing approaches that were designed for entirely different contexts. On our part, we have provided relevant prior works in the domain of human learning, our area of focus for this paper, and provided discussion in this particular context.

审稿意见
4

This paper explores the use of RL agents as a mechanism for kickstarting the training of automated teachers. Concretely, the work studies the problem of generating a useful curricula for the purpose of generating data and training teachers, without reliance on either domain-specific experts or actual students. To achieve this goal, the paper frames the problem in terms of a combination of unsupervised environment design and task sequencing. First, an exploration phase is carried out in which an RL algorithm interacts with an environment for some amount of time to collect trajectories of possible completions of a given task; from this data, a task difficulty (cθc_\theta) and occupancy distribution (ρTθπ)(\rho_{\mathcal{T}^\theta}^\pi) are computed. The task difficulty is determined by the time taken for an algorithm's performance to stabilise in a given task. Then, a second phase (called the "exploitation" phase) is carried out using these computed metrics to systematically construct a task sequence that starts out easy and gets progressively harder by moving through similar tasks (as determined by occupancy similarity). An experimental study is conducted involving real people that were tasked with completing tasks in the Jumper and Emergency Response games, where the curricula is generated according to the proposed method compared to a random training phase, no training phase, and in select experiments, a hand-crafted curriculum.

优缺点分析

__ Strengths __

  • Clear focus: The starting point of the work is that generating an appropriate curriculum can held people learn faster. This is a clear goal to pursue and allows the narrative and paper to orient itself entirely in pursuit of this focal point.
  • Pursuit of an important challenge: Developing methods that can aid in teaching people has a high potential for positive impact.
  • Human study: The paper's primary experimental study involves real people, and the findings are compelling. The strength of the evidence matches the strength of the claims made (barring some framing questions I have below). The experimental design went as far as to include a hand-crafted curriculum to compare against.

__ Weaknesses __

  • [Formatting] The formatting is sloppy at several points; one of the plots is leaking off of the page (bottom of page 9), and some of the text is formatted oddly at the bottom of page 6.
  • [Framing] There are elements of the framing of the problem and the design of the method that are questionable. Concretely, the use of cθc_\theta as a measure of task difficulty clearly cannot apply in general---determining task difficulty has itself been an active research area (see, for instance, "How hard is my MDP?" by Maillard et al.), and making use of an average point of stabilization is an ad-hoc heuristic that can clearly break down. That is, suppose algorithm A1 happens to explore in such a manner that it is systematically disposed to level off in highly-stochastic MDPs, regardless of the difficulty of the MDP; then cθc_\theta ends up measuring the degree of stochasticity present (and so on, we could imagine choosing any arbitrary characteristic of the environment to influence cθc_\theta at will). In this way, cθc_\theta is not algorithm-agnostic, but rather changes depending on the subtleties of the RL algorithm used. As a result, it is unclear whether these algorithm-specific subtleties will also extend to how people learn:" in general I am quite skeptical that they will. Similarly, the choice to use the occupancy measure for determining task similarity is again a potentially questionable choice---other task metrics have been explicitly developed (see Definition 1 by Lecarpentier et al.), and it is not clear again whether this choice will work in general.
  • [Motivation for PERM-H]: Additionally, the move to PERM-H could be given deeper justification: at present, it is stated that "We modified PERM’s original assumption that optimal learning occurs when δ=a\delta = a to δ=ϵa(ϵ1.0)\delta = \epsilon a (\epsilon ≥ 1.0), accommodating potentially faster human learning rates...", but this is left as is. A slightly expanded discussion of why this change is important will strengthen the use of PERM-H over PERM.
  • [Missing connection to work on pedagogy]. Additionally, work on understanding the nature of pedagogy in an RL context feels important to understanding the best long-term path forward for making use of automated systems in education. For example, work by Ho et al. reveals a fundamental difference in the property of showing a desired behavior vs. doing the behavior. I believe nuances of this sort play an important role in designing curricula like the kind proposed in the present paper, and believe an expanded discussion is needed.
  • Lastly, it is likely that there are nuances about how individual students learn that are important to incorporate into the design of curricula (as the paper mentions throughout). It is unclear what the path might be long-term for both being sufficiently mindful of these nuances, while also trying to make use of methods like the present one. In my opinion, the paper will be considerably strengthened with a deeper discussion at the end to comment on how to overcome this issue.

References:

  • Maillard, O. A., Mann, T. A., & Mannor, S. (2014). How hard is my MDP?" The distribution-norm to the rescue". Advances in Neural Information Processing Systems, 27.
  • Lecarpentier, E., Abel, D., Asadi, K., Jinnai, Y., Rachelson, E., & Littman, M. L. (2021, May). Lipschitz lifelong reinforcement learning. In Proceedings of the AAAI Conference on Artificial Intelligence (Vol. 35, No. 9, pp. 8270-8278).
  • Ho, M. K., Littman, M., MacGlashan, J., Cushman, F., & Austerweil, J. L. (2016). Showing versus doing: Teaching by demonstration. Advances in neural information processing systems, 29.

问题

My questions are largely a summary of a few of the weaknesses pointed out above:

Q1: How does pedagogy fit into this research agenda more broadly?

Q2: What do you perceive as the limitations to the adopted task-difficulty and task-similarity metrics? Where will they break down, and what does this imply about the potential of automated curriculum design for generating data for automated teaching?

Q3: In what ways can methods like this be mindful about the nuances that separate how actual students learn with how RL algorithms learn to ensure a positive outcome for the students? (I recognize this is discussed already, but I believe a deeper discussion is warranted)

局限性

Yes, I believe the work identifies relevant limitations

最终评判理由

Overall, the paper presents initial evidence that a thoughtfully-designed mechanism for generating curriculum can warm-start teachers more effectively. The primary evidence of the work is a human study in which the generated curricula (used to train teachers) effectively matched the performance of hand-designed curricula.

I had two primary concerns about the work:

  1. Defining task difficulty has been a long-standing open research question, with no consensus answer. My worry was that the proposed task difficulty metric is limited, and that these limitations will eventually limit the applicability of the overall method. I stand by most of this, though I note that after a back-and-forth with the authors, they have convinced me that the task difficulty measure is good enough to demonstrate the validity of their warm-starting method, which I sympathize with. It also seems reasonable (though not without some complication) that should a consensus task difficulty metric be designed, it could replace the present one with relatively little issue.

  2. Second, as with other reviewers, I was worried about whether the curricula that are thought to be useful for RL agents will also in general be useful for people. Again, I stand by parts of this worry as part of this broader research program, but naturally the evidence of this paper indicates that people do benefit over the relevant baselines.

I believe there are many positive aspects to the paper, and with the changes indicated (fixing formatting, added context reflecting the above two concerns and the other reviewers' points), I lean toward accept.

格式问题

Yes, there are several formatting issues with the paper. The largest one is the plot leaking off the page on page 8.

作者回复

We thank the reviewer for their in-depth review and feedback. We are glad that the reviewer found our work an important challenge and the potential for impact. We apologise for the formatting errors and will ensure proper formatting in the next iteration. Here are our discussion on the long-term prospects of our work:

1. On the validity of convergence-based difficulty metrics (cθ) and occupancy measures for task similarity, citing algorithm-dependence issues and asking about limitations for automated curriculum design. Where will they break down, and what does this imply about the potential of automated curriculum design for generating data for automated teaching?

We acknowledge these metric limitations while emphasizing their practical effectiveness for curriculum design.

[Convergence-based difficulty]: While algorithm-dependent, we mitigate biases through averaged statistics across multiple PPO runs and careful task verification. Our designed tasks allow validation against known complexity features (Figure 16), showing strong correlation between our metrics and intended task difficulty.

[Occupancy measures for similarity]: These capture behaviorally relevant patterns essential for knowledge transfer. Tasks requiring similar state-action sequences (e.g., treating asthma patients with specific medications) share transferable knowledge. Our human validation (r=.490 correlation) demonstrates meaningful alignment, sufficient for effective curriculum generation.

[Breakdown conditions]: Our choice of metrics would likely break down as we progress towards more abstract domains, where curriculum demands a more nuanced understanding of the learning progress. For example, using a single dimension for task difficulty will likely break down when the task involves a complex combination of different abilities to execute (e.g. language abilities and logical reasoning in high school curriculum), preventing a more targeted approach for curriculum design.

[Implications for automated curriculum design]: Rather than fundamental limitations, these represent current design challenges. The key insight is that moderate fidelity suffices for warm-starting teacher algorithms and perfect metrics aren't required. This aligns with our stand that while RL agents provide useful cold-start data, the ultimate goal should be a human-centric design with more human data. Future improvements should focus on environment design that better captures human-centric factors (cognitive load, attention) while maintaining the practical advantages of automated data generation. Our Emergency Response environment is an example of how sophisticated medical procedural knowledge can be designed into an environment that still produces learning gains.

The broader potential remains strong: automated curriculum design provides scalable foundations that human data can subsequently refine.

2. Motivation for PERM-H

Our changes to PERM is motivated by prior work (Tsividis et al, 2017) that humans learn at a rate higher than artificial agents. Through pilot studies, we arrived at this formulation due to our observations that adjusting the rate of difficulty increase alleviates boredom and frustrations in our human subjects.

3. Incorporating Individual Differences and Mindful RL-Human Gap Management

Current foundation supports individual adaptation with clear extension pathways

[Adaptive baseline]: Our algorithms are inherently adaptive, adjusting to individual performance patterns without requiring prior demographic modeling. This addresses cold-start scenarios where student characteristics are initially unknown, allowing the system to discover individual differences through interaction.

[Future individualization]: Extensions could model multi-dimensional learner profiles (learning pace, preferred modalities, attention spans, prerequisite knowledge) by expanding our similarity metrics to capture these factors. RL agents could be trained with varied "learning personalities" to generate diverse curricula templates that accommodate different learning styles.

Two perspectives to managing RL-human learning differences

[Bridge the gaps through pedagogically-informed design]: The first perspective suggests that one should manage these gaps in order to improve the outcomes for humans. Taking a top-down perspective from learning sciences, we can design environments and teacher models that better capture human-centric learning factors. For example, incorporating cognitive load theory through task complexity constraints, or implementing spacing effects by restricting how frequently similar tasks appear. In this work, we have taken extra care to designing the Emergency Response game, where we managed to translate medical knowledge to an environment which both RL and Humans can demonstrate learning.

[Leverage differences as educational advantages]: The second perspective embraces these differences as potentially beneficial. Successes in complex domains like Dota2 (OpenAI Five) and Go (AlphaGo's move 37) demonstrate that RL learning processes can unlock creative approaches that humans might overlook. Research could explore when these differences benefit human learning and under what conditions such phenomena occur.

To be clear, we adopted the first perspective in this work, where we took pedagogical theories to inform our teacher algorithm and investigated the gaps in the context of our selected metrics. We show here that while the metrics are not perfectly aligned, the educational outcomes are prevalent in our students.

Practical implementation strategy

The key insight is starting with universal learning principles (difficulty progression, knowledge continuity) that work across individuals, then progressively personalizing as more data becomes available. This provides immediate practical value while building foundations for sophisticated individualization, ensuring positive outcomes through validated pedagogical principles rather than relying solely on RL-derived patterns.

4. How does pedagogy fit into this research agenda more broadly?

Our work advances computational pedagogy by solving a fundamental bootstrapping problem: effective teacher algorithms require extensive human learning data, yet collecting such data is prohibitively expensive.

[Pedagogical contribution]: We demonstrate that RL agents can serve as pedagogical proxies, capturing sufficient learning dynamics to warm-start sophisticated teacher algorithms. This opens previously inaccessible pedagogical approaches in domains that are new, such as task difficulty measurements in the environments we have designed.

[Broader research agenda]: This enables two complementary research directions. First, enriching RL-generated data with pedagogical nuances. Ho et al.'s "showing vs doing" distinction exemplifies this; RL agents naturally exhibit "doing" behaviors (exploitation without considering educational value) that differ from demonstrations with educational intent. Teacher algorithms aware of this distinction can leverage both trajectory types appropriately.

Second, scaling sophisticated pedagogical models that were previously data-prohibitive. Our framework accommodates diverse pedagogical theories (Zone of Proximal Development, Spiral Curriculum) and can support more complex approaches incorporating spacing effect (Ebbinghaus 1948) and scaffolding via expertise-reversal effect (Kalyuga et, and individual differences as they develop.

[Key insight]: Rather than replacing pedagogical expertise, our approach democratizes access to data-hungry pedagogical models. This creates opportunities for educational researchers to test and deploy sophisticated theories without massive upfront data collection, accelerating the translation of pedagogical research into practical educational technologies.

The ultimate vision is pedagogically-grounded AI that starts with universal learning principles and progressively personalizes through human interaction.


Ebbinghaus, H. (1948). Concerning memory, 1885. In W. Dennis (Ed.), Readings in the history of psychology (pp. 304–313). Appleton-Century-Crofts. https://doi.org/10.1037/11304-034

Kalyuga, S., Ayres, P., Chandler, P., Sweller, J. (2003). The expertise reversal effect. Educational Psychologist, 38(1), 23–31.

Silver, D., Huang, A., Maddison, C. et al. Mastering the game of Go with deep neural networks and tree search. Nature 529, 484–489 (2016). https://doi.org/10.1038/nature16961

OpenAI (2019). Dota 2 with Large Scale Deep Reinforcement Learning. 10.48550/arXiv.1912.06680.

评论

I thank the authors for their extensive and thoughtful rebuttal. I have read the other reviews and their responses, and have a few follow ups.

First, I'd like to discuss the task-difficulty measure a bit further. I can appreciate that the design of this measure is largely in service of generating a meaningful curriculum. However, conceptually, time-taken to reach convergence (in expectation) is clearly an ill-fit for task difficulty, in my opinion: consider a highly challenging domain that would require on the order of billions of steps before seeing positive signal. Convergence will occur for most algorithms at time step zero, since no signal is reasonably seen over the interval studied. How long do we run learning algorithms until deciding they have converged? In this example we will likely mistakenly attribute convergence to the region of learning prior to experiencing anything meaningful. Further, we can imagine extensions of this environment where, for each choice of n, at expanding intervals of length 2^n the task richness increases (for instance, the reward scale achievable grows with 2^n). As such, there is a doubling effect to the needed horizon used in order to identify convergence (further, many sensible algorithms may never converge). Furthermore, most algorithms come with implicit step-size annealing schedules that enforce convergence. I mention these comments only to point out again that task difficulty is its own conceptually rich and unanswered research question, and I worry about over-simplifying this matter in the inner-loop of this broader research agenda. At the same time, I acknowledge that designing an appropriate measure of task-difficulty is its own significant open research question (with no consensus answer), that is not necessarily in focus here.

This brings me to two follow up questions I would love to hear the authors' thoughts on::

Q1: To what extent do the authors believe their overall approach is agnostic to this precise choice for measuring task difficulty? If the proposed measure ends up being of an incorrect design, how much will it impact the overall approach?

Q2: To me, this also reinforces another question raised by reviewer 27Ra, paraphrased as "Why can we model students as a standard RL learning agent?" In what sense is a task-difficulty measure, designed for specific learning algorithms, well suited to generate curricula for warm-starting teachers that will ultimately be deployed for use in training people?

I am overall sympathetic to the authors' case, and time-dependent, I would love to hear their thoughts on the above two questions.

评论

We thank the reviewer for their thoughtful comments and appreciate the opportunity to engage with these fundamental questions about task difficulty measurement and its application to human learning.

The reviewer raises valid concerns about using convergence time as a task difficulty measure, particularly in scenarios where algorithms might falsely appear to converge on extremely challenging tasks. We acknowledge that our SimMAC approach may exhibit such limitations under the conditions described. However, in our specific experimental environments, we found this metric to be sufficient and were able to validate it against the task complexity tree we developed for Emergency Response (Figure 16). This validation gave us confidence to proceed with human trials.

1. Regarding the robustness of our approach to imperfect difficulty measures:

Through our study, we found that our approach seems to be robust to imperfect difficulty estimations in some ways:

Multi-metric resilience: SimMAC combines both difficulty and similarity measures. If one metric provides poor signals, the other can still contribute meaningfully to curriculum generation. This redundancy helps maintain performance even when difficulty estimation is imperfect.

Graceful degradation: In worst-case scenarios where our model fails entirely, the curriculum defaults to random ordering. While our experiments show random curricula perform no better than control conditions, prior work has demonstrated that random curricula remain competitive baselines, providing a reasonable lower bound.

Warm-start philosophy: Our approach is designed as a warm-start solution. The ultimate goal is to replace initial RL-derived data with more accurate models trained on our target population. From this perspective, a "good enough" initial approximation provides practical value in the broader learning pipeline.

Priming with Pedagogical model: We believe the key to effective curriculum generation lies primarily in the pedagogical model itself. Our results suggest that even minimal alignment between RL agents and humans can provide sufficient signal to support our selected pedagogical models (Zone of Proximal Development and Spiral Curriculum).

2. Regarding the generalizability from RL to human learning:

We want to clarify an important distinction: while we use RL agents to measure task difficulty, we make no assumptions that humans learn identically to RL agents. Instead, we hypothesize that certain fundamental aspects of task difficulty (e.g. task complexity, required skill combinations, and clarity of learning objectives) may generalize across different learning systems.

Our human subject experiments provide empirical evidence supporting this hypothesis. Teacher algorithms trained on RL-generated data successfully informed effective curricula for human learners, suggesting that the underlying difficulty structure captured by our RL measurements contains information relevant to human learning.

In summary, we view our contribution as demonstrating that approximate, RL-derived task difficulty measures can meaningfully inform human curriculum design despite their inherent limitations. While we agree that developing more sophisticated difficulty measures remains important future work, our results suggest that the practical benefits of curriculum generation are robust enough to justify this approach even with imperfect difficulty estimation.

The core insight is that perfect difficulty measurement is not required for useful curriculum generation; reasonably good approximations, when embedded within sound pedagogical frameworks, can still produce meaningful learning benefits for human students.

评论

I again would like to thank the authors for such a thoughtful response.

Re: 1. Robustness to imperfect difficulty measures

I sympathize with their points about the design of the task metric: the initial testing of the task metric was sufficiently convincing to use the task metric in human trials, which also yielded desirable performance.

I also appreciate the point regarding a graceful degradation that backs off to a random curriculum. Of course, such design choices can likely be iterated on in future work, but this is clearly out of scope for the present paper.

Overall, I am swayed that the task metric can act as a useful starting point for warm starting curricula, and that the overall proposed method can likely improve if other better task metrics were to be designed later on. All that being said, I do stand by the limitations I noted regarding the design of this task difficulty metric cθc_\theta.

Re: 2. Generalizability from RL to human learning:

This makes sense to me as well, and I grant that the present work does provide initial signs that support the stated claim:

The core insight is that perfect difficulty measurement is not required for useful curriculum generation; reasonably good approximations, when embedded within sound pedagogical frameworks, can still produce meaningful learning benefits for human students.

Naturally there is always more to do to further the science, and the fact that there is room ahead to strengthen the work by exploring deeper should not necessarily be a knock on this work as it stands.

In light of the discussion, I lean in favor of accepting the work, and I will raise my score.

审稿意见
5

The manuscript presents two algorithms to deal with the problem of cold start in teacher algorithms. Those algorithms use RL to mimic the behavior and learning of humans. The goal is to generate synthetic training data, which is then used to initialize and optimize curriculum sequencing algorithms before real human data becomes available.

优缺点分析

STRENGTHS:

  • The paper is well-organized, and provide the necessary details.
  • Two algorithms are put forward with their pros and cons well-described and motivated
  • The performed evaluation is very solid, with two different environments and rigorous statistical analysis.
  • The appendices are most informative and comprehensive.
  • The full Jumper environment is given with the supplementary materials

If any weakness is to be listed, I would say that the framework is still in the exploration phase because the environments are relatively simple, and their domains do not heavily involve abstract concepts. The Emergency Response Environment has not been included in the supplementary materials due to file size. Maybe a link to anonymous download somewhere else would have been a good idea.

问题

  • How could the RL approach tackle diversity in learners, in terms of backgrounds, learning capacities, disabilities, etc.? How can these differences be modeled?
  • What would be the main difficulty to employing this approach in more abstract domains?
  • Is there room for a third algorithm that deals with the limitations of PERM_H and SimMAC? How would it be shaped?

局限性

In general, yes. However, I would like to see more details as to how the RL agents can represent diverse learners and not just focus on the majority for which most data will be generated.

最终评判理由

I acknowledge the effort that authors have put on explaining the raised concerns and to answers all my questions and those from my fellow reviewers. I am satisfied with their answers; thus, I reiterate that this is a solid paper that merits acceptance.

It's a pity that reviewer de4j didn't follow on the discussion. An acknowledgement from their side on whether the authors were right or not would have been beneficial to settle the issue he/she raised.

格式问题

no problems

作者回复

We thank the reviewer for the positive review and for recognizing the importance of our work. We are encouraged that the reviewer saw our evaluation as solid and well-detailed.

1. How could the RL approach tackle the diversity in learners, in terms of backgrounds, learning capabilities, disabilities, etc? How can these differences be modeled?

We appreciate this important question about accommodating diverse learners, which is indeed a core challenge in personalized education.

In the current work, our proposed algorithms adapt to individual differences through performance-based inference

[Ability-focused design]: Both PERM-H and SimMAC continuously adjust to individual students by inferring their current ability levels from performance feedback and selecting appropriate next challenges. This responsiveness naturally accommodates different learning rates, prior knowledge, and capabilities without requiring explicit demographic modeling.

Our human studies demonstrate this flexibility across participants with varying gaming experience and medical backgrounds (Sections 6.1, A.4). Importantly, our approach improved learning outcomes regardless of participants' initial prior knowledge levels, suggesting robustness to individual differences in our tested domains.

[Current framework handles basic diversity, with clear pathways for complex cases]

Without a doubt, there is room for greater levels of personalization (for more nuanced considerations like cognitive differences, learning disabilities) for which we propose extensions to our current work below.

[Enhanced teacher models]: Teacher models could be further extended to more sophisticated models. Prior work in Doroudi et al's (2019) survey showed that models that were backed by pedagogy-motivated models performed better than data-driven approaches. As an example, Item Response Theory, which underlies PERM-H, offers extensions for modeling multiple ability dimensions simultaneously (e.g., language proficiency and logical reasoning).

[Population-specific fine-tuning]: Following transfer learning principles from machine learning, our RL-pretrained teacher models can be fine-tuned on specific populations to accommodate specialized needs while retaining the general learning patterns.

Our two-stage approach naturally supports this progression: RL data provides general learning patterns, then human data from specific populations can refine the models for targeted accommodation. This maintains the cold-start benefits while enabling specialized adaptation as needed.

2. What would be the main difficulty to employ these approaches in more abstract domains?

We anticipate two challenges in deploying our framework in more abstract domains:

[Environment design complexity]: Abstract domains like philosophy, mathematics, or critical thinking require natural language interactions and sophisticated reasoning situations to train. We would have to utilize LLMs to augment our trainers to generate appropriate situations at the right time.

[Learning process modeling]: Our approach relies on observing RL agents' progression patterns to capture learning dynamics. In abstract domains, this may not be sufficient, as learning can also involve certain "intrinsic" understanding beyond "extrinsic" knowledge/skills.

[LLMs as learning proxies?]: For abstract domains like mathematics or logic, large language models may serve as more appropriate proxies for human learners than traditional RL agents. RL, unlike pre-trained LLMs, grows while exploring the environment, presenting a good simulation of learning. Recent work in cognitive modeling (Binz et al 2024) through language models (foundation models for human decision making) shows promise.

[Transferable principles from our current work]

Our paper's fundamental insight is that artificial agents can capture useful learning patterns for curriculum design and that moderate alignment suffices for effective teaching. This lays the foundation for research into artificial agents generating data for teacher algorithms for humans. The technical implementation would require domain-specific innovations, but our two-stage framework provides a general methodology for bootstrapping personalized learning systems across diverse educational contexts.

3. Is there room for a third algorithm that deals with the limitations of PERM_H and SimMAC? How would it be shaped?

Yes, we think that there is a possibility of building more sophisticated models that consider the science of learning principles. Then, the challenge would be to see if there are methods or clever design of the exploration stage (be it on the environment design front, or the MDP formulation front) that can be used to address the data needs of these models. As research into leveraging RL as data-generators increases, we envision more models that are nuanced in their understanding of the RL-human gap, and bridge them through design.


[1] Binz, Marcel, et al. "Centaur: a foundation model of human cognition." arXiv preprint arXiv:2410.20268 (2024).

评论

I thank the authors for the effort they've put on explaining the raised concerns and to answers all my questions and those from my fellow reviewers. I am satisfied with their answers to my questions and thus, I still think that this is a solid paper that merits acceptance.

Said that, I am closely following the discussion with other reviewers on topics I am not so knowledgeable, and will take those discussions into account to confirm my rating tomorrow. I therefore encourage the authors to fully engage with the other reviewers questions (as they are doing with de4j).

审稿意见
3

This paper investigates a novel approach to addressing the cold-start problem in AI-powered teaching systems by using Reinforcement Learning (RL) agents to bootstrap training data for teacher algorithms. These algorithms are designed to personalize learning by adaptively sequencing tasks based on student progress. Because collecting extensive human learning data is costly and time-consuming, the authors propose leveraging RL agents to generate initial training curricula, which can later be refined with human data. The authors introduce a two-stage framework where RL agents first generate task sequences to train teacher algorithms. They present two new algorithms under this framework: a human-friendly adaptation of PERM for domains with infinite scenario possibilities, and SimMAC, a novel task sequencing algorithm for domains with a discrete and finite set of tasks. The effectiveness of this approach is demonstrated through human subject studies in two distinct environments: Jumper and Emergency Response. Results show that RL-initialized teacher algorithms can match or outperform baseline methods and even compete with expert-designed curricula. However, the authors also observe a mismatch between RL agent behavior and human learning patterns, suggesting a need for improved alignment. Ultimately, the paper offers a promising direction for making adaptive, personalized learning systems more accessible, especially in early-stage development, and encourages future research at the intersection of RL and human pedagogy.

优缺点分析

Strength:

The paper presented a very interesting application of RL in interactive teaching of human students. The proposed methodology is demonstrated on Jumper and Emergency Response.

Weaknesses:

The paper is lacking a solid justification on human/student models. Why can we model student as a standard RL learning agent? What if there is significant difference between student learning process and ML learning process? How to justify the benefit really comes from the proposed methodologies designed in this paper?

Why exploration stage helps? Or more specifically, why synthetic data that simulates RL learning process is helpful to enhance interactive teaching process? Other than empirical results, are there theoretical insights behind that?

问题

  1. What if the human student learning process differs from RL learning? How to justify that these two process are similar?

  2. Why exploration stage/synthetic data is helpful? Could authors provide some justification of that?

局限性

No

最终评判理由

Thanks for your response. Your explanation makes intuitive sense to me. However, I am still not convinced due to lack of theory. I agree this paper studied an interesting problem and might be helpful in certain practical scenarios, but not having solid theoretical justification is really a key problem. Therefore, I will need to keep my original score

格式问题

None

作者回复

We thank the reviewer for their time in reviewing, and welcome the questions.

1. Why can we model students as a standard RL learning agent? What if there is a significant difference between the student learning process and ML Learning process? What if the human student learning process differs from RL Learning? How to justify that these two processes are similar?

We appreciate this fundamental question about the validity of using RL agents as proxies for human learners.

Our claim is that we do not need perfect equivalence between RL agents and human learners. We need enough similarity to generate effective curricula.

This is because effective curriculum design requires capturing learning progression patterns and task difficulty relationships, not perfective cognitive modeling of human learners. We explicitly acknowledge differences between RL and human learning while showing that moderate alignment is sufficient for warm-start data generation.

[Empirical evidence demonstrates sufficient alignment across the following key dimensions]

Task similarity patterns: Section 6.3 shows moderate positive correlation (r=.490, p<.001) between RL and human inter-task similarity measures across 287 task pairs in the Emergency Response domain.

Difficulty ranking consistency: Both RL agents and humans consistently agreed on task difficulty rankings in the Jumper environment, with RL agents reaching comparable difficulty levels to human-designed curricula (Figure 3).

Learning progression patterns: RL agents exhibit similar progression dynamics: starting from low performance and gradually improving through structured practice, mirroring fundamental human learning characteristics.

[Human studies validate the practical effectiveness despite imperfect modeling]

Our RL-initialized curricula (PERM-H, SimMAC) matched expert-designed curricula and significantly outperformed random baselines in human studies (Figures 1-2). This demonstrates that the captured learning patterns translate to effective human learning outcomes.

[Our framework is designed to handle modeling limitations]

The two-stage approach explicitly addresses this concern: RL data provides initial bootstrapping, then human interaction data supplements and eventually replaces RL data for better alignment. This design acknowledges that RL is an approximation while leveraging its benefits for cold-start mitigation.

The strong empirical outcomes validate that moderate alignment is sufficient for addressing the cold-start problem in personalized education systems.


2. Why is having exploration stage/synthetic data helpful? Could authors provide some justification of that?

The exploration stage solves a critical practical and ethical problem

[Cost barrier:] Traditional teacher algorithms require extensive human learning data before becoming effective. Bassen et al. (2020) demonstrated this challenge, requiring 900 man-hours for their RL teacher to converge (lines 80-87), creating prohibitive deployment costs.

[Ethical concerns:] Early learners in cold-start systems receive poor instruction while the algorithm learns, raising fairness concerns about subjecting students to ineffective teaching during the learning phase.

RL agents generate learning patterns that transfer effectively to humans

Scalable pattern generation: RL agents can generate extensive training trajectories across diverse difficulty levels and task combinations without human cost, capturing fundamental learning dynamics like difficulty progression and knowledge transfer relationships.

Validated transfer: Our empirical results demonstrate this transfer works in practice. Both PERM-H and SimMAC, trained solely on RL-generated data, significantly outperformed random curricula and matched expert-designed sequences in human studies (Figures 1-2).

Concrete evidence shows synthetic data captures relevant learning dynamics

Difficulty alignment: RL agents reached difficulty levels comparable to humans in the Jumper environment (Figure 3), suggesting they capture meaningful challenge progression patterns.

Task relationship modeling: In Emergency Response, RL-derived task similarity patterns showed meaningful correlation with human patterns (r=.490, p<.001), indicating successful capture of knowledge transfer relationships.

[The exploration stage provides competent initialization without human cost]

The exploration stage essentially "pre-trains" our teacher algorithms on synthetic learning trajectories, eliminating the cold-start problem where early learners receive poor instruction. This provides a competent starting point that can be refined with human data as it becomes available, combining scalability with adaptability.

评论

Dear Reviewer 27Ra, just to let you know we will be happy to answer any further questions you may have on the paper! We also invite you to consider our discussion with the other reviewers, and hope to have a fruitful session with everyone.

最终决定

This paper explores how reinforcement learning agents can be used to warm-start teacher algorithms, with the goal of improving the efficiency and effectiveness of human learning. The authors develop a framework that bridges machine learning and education, where RL agents generate initial teaching strategies that can later be refined for human learners. Human-subject experiments are conducted to demonstrate the potential of this approach.

Overall, the main strengths of the paper are the importance and difficulty of the topic, as well as the use of human studies to support the findings. The main reservations include: (1) the choice of task difficulty metric, (2) the justification for using RL-based learning to model human learning, and (3) the level of engagement with the curriculum learning literature (including the design of baselines). For (1) and (2), while the choices are not strongly theoretically justified, the authors show that they “work” in human studies, which could indicate meaningful connections. For (3), while the authors argue that curriculum learning methods generally require large amounts of data and are thus infeasible in human contexts, Reviewer de4j notes that it is not clear why curricula could not simply be built using RL agents “pretending” to be humans. This would follow the same line of reasoning as the authors’ use of RL to model human learning and would provide a natural way to incorporate the existing curriculum learning literature into human learning. For this point (3), I have read the author comment/rebuttal/mark and take a scan of the paper, I tend to agree with reviewer de4j's point. It's possible we are missing important technical pieces, but the current presentation (including the follow-up responses) do not make it clear.

In the reviewer–AC discussion, two reviewers remained borderline positive (Reviewer Chjm clarified that his/her assessment should be interpreted as borderline accept -- he/she is reluctant to use the borderline rating), but they were hesitant to endorse acceptance, while the more reserved reviewers remained firm in their rejection. Given that I share some of these reservations, we recommend rejection in its current form, but hope the authors find the reviews helpful for future revisions.