Formalized Run-Time Analysis of Active Learning -- Coalgebraically in Agda

Fuente: arXiv
Saved in:
Bibliographic Details
Main Author: Wißmann, Thorsten
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912911564210176
author Wißmann, Thorsten
author_facet Wißmann, Thorsten
contents The objective of automata learning is to reconstruct the implementation of a hidden automaton, to which only a teacher has access. The learner can ask certain kinds of queries to the teacher to gain more knowledge about the hidden automaton. The run-time of such a learning algorithm is then measured in the number of queries it takes until the hidden automaton is successfully reconstructed, which is usually parametric in the number of states of that hidden automaton. How can we prove such a run-time complexity of learning algorithms in a proof assistant if we do not have the hidden automaton and the number of states available? In the present paper, we solve this by considering learning algorithms themselves as generalized automata, more specifically as coalgebras. We introduce formal and yet compact definitions of what a learner and a teacher is, which make it easy to prove upper and lower bounds of different kinds of learning games in the proof assistant Agda. As a running example, we discuss the common number guessing game where a teacher thinks of a natural number and answers guesses by the learner with `correct', `too high', or `too low'. To demonstrate our framework, we formally prove in Agda that both the lower and upper bound on number of guesses by the learner is $\mathcal{O}(\log n)$, where $n$ is the teacher's secret number.
format Preprint
id arxiv_https___arxiv_org_abs_2602_16427
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Formalized Run-Time Analysis of Active Learning -- Coalgebraically in Agda
Wißmann, Thorsten
Formal Languages and Automata Theory
The objective of automata learning is to reconstruct the implementation of a hidden automaton, to which only a teacher has access. The learner can ask certain kinds of queries to the teacher to gain more knowledge about the hidden automaton. The run-time of such a learning algorithm is then measured in the number of queries it takes until the hidden automaton is successfully reconstructed, which is usually parametric in the number of states of that hidden automaton. How can we prove such a run-time complexity of learning algorithms in a proof assistant if we do not have the hidden automaton and the number of states available? In the present paper, we solve this by considering learning algorithms themselves as generalized automata, more specifically as coalgebras. We introduce formal and yet compact definitions of what a learner and a teacher is, which make it easy to prove upper and lower bounds of different kinds of learning games in the proof assistant Agda. As a running example, we discuss the common number guessing game where a teacher thinks of a natural number and answers guesses by the learner with `correct', `too high', or `too low'. To demonstrate our framework, we formally prove in Agda that both the lower and upper bound on number of guesses by the learner is $\mathcal{O}(\log n)$, where $n$ is the teacher's secret number.
title Formalized Run-Time Analysis of Active Learning -- Coalgebraically in Agda
topic Formal Languages and Automata Theory
url https://arxiv.org/abs/2602.16427