# Invited Talks

## Language

### Heather Burnett (CNRS & Paris Diderot)

**Title:** Linking Sociolinguistic Variation and Strategic Action with Game Theory and Video Games.

**Abstract:** In this presentation, which is joint work with Gabriel Thiberge (CNRS, Paris Cité), we present new formal and experimental methods to investigate the link between language and human behavior, in particular, the relationship between sociolinguistic variation and strategic action. Much research in sociolinguistics and linguistic anthropology has shown that people take into account sociolinguistic variants (grammatical alternatives that are used by different subgroups of a speech community (Labov 1972)) in deciding how to act in a strategic context; in other words, people act differently towards others depending on how they talk. This is a very general phenomenon, but it has been most closely studied in the context of linguistic discrimination, i.e. the observation that speakers of non-standard linguistic varieties are often treated worse by people in positions of power than those speaking standard/prestige varieties (see Baugh 2017, Craft et al. (2020), among many others). In this talk, we present a formal model of linguistic discrimination building on recent approaches to social meaning in game-theoretic pragmatics (eg. Burnett 2019, 2023) and then we test this model using an experimental paradigm based on video games.

__References__

*The Oxford handbook of language and society*, 349-368.

*Annual Review of Linguistics*,

*6*, 389-407.

*Meaning, Identity, and Interaction: Sociolinguistic Variation and Change in Game-theoretic Pragmatics*. Cambridge University Press.

*Linguistics and Philosophy*,

*42*, 419-450.

*Language in society*,

*1*(1), 97-120.

### Stephanie Solt (ZAS Berlin)

**Title:** On Amounts and Measures.

**Abstract:** Click here.

## Logic & Computation

**Balder ten Cate (University of Amsterdam)**

**Title:** Homomorphism Counts, Logics, and Query Algorithms.

**Abstract:** A homomorphism is a structure-preserving map from a structure A to a structure B. The existence or non-existence of certain incoming or outgoing homomorphisms can reveal a lot of interesting information about a structure. For instance, a graph is 2-colorable if and only if it has a homomorphism to the 2-element clique, if and only if no cycle of odd length has a homomorphism to A. Homomorphism counts can reveal even more information. In fact, a classic result by Lovasz states that a finite structure A is characterized up to isomorphism by the number of homomorphisms that it has from all finite structures. Similarly, Dvorák has shown that, for certain fragments of first-order logic, indistinguishability can be characterized as having the same number of homomorphisms from a restricted class of structures. In particular, whether a formula from such a fragment is true or false in a structure A is completely determined by the number of homomorphisms A has from structures belonging to the class in question. In recent work, Chen et al further refine these connections by introducing the concept of "query algorithms", that is, algorithms that can interact with a given structure only by asking homomorphism-count queries. In particular, they study the question of how many homomorphism count queries such an algorithm needs to make in order to determine whether a given formula is true or false. In this talk, we review these and other recent results that connect homomorphism counts, logics, and query algorithms. We will show that homomorphism counts provide an interesting perspective from which one can study the expressive power of different logical languages.

### Nina Gierasimczuk (Technical University of Denmark)

**Title (UPDATED):** Inductive Inference and Epistemic Modal Logic

**Abstract (UPDATED): **This overview talk is concerned with a link between inductive inference and dynamic epistemic logic. I will present a synthetic view on several contributions: inductive truth-tracking properties of belief revision policies seen as belief upgrade methods; topological interpretation and characterization of inductive inference; discussion of the adequacy of the topological semantics of modal logic for characterizing inductive inference. I will briefly present the topological Dynamic Logic for Learning Theory. Finally, I will discuss several surprising results obtained in computational inductive inference that challenge the usual understanding of certainty, and of rational inquiry as consistent and conservative learning.** **

See: Nina Gierasimczuk. Inductive inference and epistemic modal logic. In Bartek Klin and Elaine Pimentel, editors, 31st EACSL Annual Conference on Computer Science Logic, CSL'23, Warsaw, Poland, Feb 13-16, 2023, volume 252 of LIPIcs, pages 2:1-2:16. Schloss Dagstuhl-Leibniz-Zentrum für Informatik, 2023. DOI