ILLC-LIRa April 2023

illc-lira@list.uva.nl

1 participants
6 discussions

LIRa session: Jon Williamson (tomorrow, WEDNESDAY, 26 April 16:30, ONLINE-ONLY)
by LIRa Seminar 25 Apr '23

25 Apr '23

Dear all, We will have our next LIRa session tomorrow, on Wednesday, 26 April 16:30. Note the unusual day: Because Thursday is a national holiday in The Netherlands we will have our session on Wednesday instead. This will be an ONLINE-ONLY session. To attend, please use our recurring zoom link: https://uva-live.zoom.us/j/89230639823?pwd=YWJuSnJmTDhXcWhmd1ZkeG5zb0o5UT09 (Meeting ID: 892 3063 9823, Passcode: 421723) You can find the details of the talk below. Speaker: Jon Williamson (University of Kent) Date and Time: Wednesday, April 26th 2023, 16:30-18:00 Note the unusual day! (Due to Thursday being a holiday.) Venue: ONLINE only (i.e. not hybrid) Title: A decidable class of inferences in first-order objective Bayesian inductive logic Abstract. This talk begins with a gentle introduction to objective Bayesian inductive logic and the main differences between this approach and Carnap's approach to inductive logic. Then we move to the question of decidability. First-order deductive logic is well known to be undecidable and this undecidability carries over to inductive logic under the standard semantics, which holds that premisses inductively entail a conclusion just when every probability function that satisfies the premisses also satisfies the conclusion. It is perhaps surprising then that a large class of inferences in objective Bayesian inductive logic turns out to be decidable. We see that decidability is achieved by reducing the general inference problem to a problem involving only quantifier-free premisses, which can be solved using a truth-table method. This reduction permits the use of Bayesian networks to provide a potentially efficient approach to inference in objective Bayesian inductive logic. Joint work with Juergen Landes & Soroush Rafiee Rad. Hope to see you there! The LIRa team

1 0

LIRa session: Jon Williamson (WEDNESDAY, 26 April 16:30)
by LIRa Seminar 21 Apr '23

21 Apr '23

Dear all, We will have our next LIRa session on Wednesday, 26 April 16:30. Note the unusual day: Because Thursday is a national holiday in The Netherlands we will have our session on Wednesday instead. This will be an ONLINE-ONLY session. To attend, please use our recurring zoom link: https://uva-live.zoom.us/j/89230639823?pwd=YWJuSnJmTDhXcWhmd1ZkeG5zb0o5UT09 (Meeting ID: 892 3063 9823, Passcode: 421723) You can find the details of the talk below. Speaker: Jon Williamson (University of Kent) Date and Time: Wednesday, April 26th 2023, 16:30-18:00 Note the unusual day! (Due to Thursday being a holiday.) Venue: ONLINE only (i.e. not hybrid) Title: A decidable class of inferences in first-order objective Bayesian inductive logic Abstract. This talk begins with a gentle introduction to objective Bayesian inductive logic and the main differences between this approach and Carnap's approach to inductive logic. Then we move to the question of decidability. First-order deductive logic is well known to be undecidable and this undecidability carries over to inductive logic under the standard semantics, which holds that premisses inductively entail a conclusion just when every probability function that satisfies the premisses also satisfies the conclusion. It is perhaps surprising then that a large class of inferences in objective Bayesian inductive logic turns out to be decidable. We see that decidability is achieved by reducing the general inference problem to a problem involving only quantifier-free premisses, which can be solved using a truth-table method. This reduction permits the use of Bayesian networks to provide a potentially efficient approach to inference in objective Bayesian inductive logic. Joint work with Juergen Landes & Soroush Rafiee Rad. Hope to see you there! The LIRa team

1 0

Joint LLAMA and LIRa session: Ekaterina Kubyshkina & Mattia Petrolo (tomorrow, Thursday, 20 April 16:30)
by LIRa Seminar 19 Apr '23

19 Apr '23

Dear all, Tomorrow at 16:30 we will have a joint LLAMA and LIRa session! This will be a *hybrid* session. If you want to attend online, please use the following ZOOM LINK, DIFFERENT THAN OUR USUAL ONE: https://uva-live.zoom.us/j/84413536364 Meeting ID: 844-1353-6364 You can find the details of the talk below. This will be a joint session together with the LLAMA seminar. Speakers: Ekaterina Kubyshkina & Mattia Petrolo Date and Time: Thursday, April 20th 2023, 16:30-18:00 Venue: ILLC seminar room F1.15 in Science Park 107 and online. Title: Creating new worlds: a PAL for excusable ignorance. Abstract. There is a lively debate in the current literature on epistemology on which type of ignorance may provide a moral excuse. A good candidate is the one in which an agent has never thought about or considered as true a proposition p. From a logical perspective, no formal analysis was provided for ignorance as an excuse. We fill this gap by providing an original logical setting for modelling this type of ignorance. In particular, we introduce a complete and sound logic in which ignorance is expressed as a primitive modality. Semantically, the logic is characterized by Kripke semantics with possibly incomplete worlds, or, equivalently, Kripke models equipped with a three-valued valuation function. Moreover, to consider the conditions of a possible change of an agent's ignorance, we will extend the setting to public announcement logic. First, we show that standard update procedures are not suitable for an adequate representation of scenarios involving excusable ignorance. Secondly, we define an original update procedure, which modifies the initial models by creating new worlds and accessibilities, instead of eliminating them. We exemplify the fruitfulness of this procedure via an intuitive example. (joint work with M. K. Pereira) Hope to see you there! The LIRa team

1 0

Joint LLAMA and LIRa session: Ekaterina Kubyshkina & Mattia Petrolo (Thursday, 20 April 16:30)
by LIRa Seminar 14 Apr '23

14 Apr '23

Dear all, We will have a joint LLAMA and LIRa session next week on Thursday, 20 April 16:30. This will be a hybrid session. If you want to attend online, please use the following ZOOM LINK, DIFFERENT THAN OUR USUAL ONE: https://uva-live.zoom.us/j/84413536364 Meeting ID: 844-1353-6364 You can find the details of the talk below. Speakers: Ekaterina Kubyshkina & Mattia Petrolo Date and Time: Thursday, April 20th 2023, 16:30-18:00 Venue: ILLC seminar room F1.15 in Science Park 107 and online. Title: Creating new worlds: a PAL for excusable ignorance. Abstract. There is a lively debate in the current literature on epistemology on which type of ignorance may provide a moral excuse. A good candidate is the one in which an agent has never thought about or considered as true a proposition p. From a logical perspective, no formal analysis was provided for ignorance as an excuse. We fill this gap by providing an original logical setting for modelling this type of ignorance. In particular, we introduce a complete and sound logic in which ignorance is expressed as a primitive modality. Semantically, the logic is characterized by Kripke semantics with possibly incomplete worlds, or, equivalently, Kripke models equipped with a three-valued valuation function. Moreover, to consider the conditions of a possible change of an agent's ignorance, we will extend the setting to public announcement logic. First, we show that standard update procedures are not suitable for an adequate representation of scenarios involving excusable ignorance. Secondly, we define an original update procedure, which modifies the initial models by creating new worlds and accessibilities, instead of eliminating them. We exemplify the fruitfulness of this procedure via an intuitive example. (joint work with M. K. Pereira) Hope to see you there! The LIRa team

1 0

CANCELLED - No LIRa session this week.
by LIRa Seminar 12 Apr '23

12 Apr '23

Dear all, Unfortunately the LIRa session tomorrow is cancelled and there will be no LIRa this week. Our next event will be a joint session with the LLAMA seminar next week, on Thursday, April 20th. kind regards, The LIRa team

1 0

LIRa session: Emiliano Lorini (ONLINE ONLY, tomorrow, Thursday, 6 April 16:30)
by LIRa Seminar 05 Apr '23

05 Apr '23

Dear all, We will have our next LIRa session tomorrow, on Thursday, 6 April 16:30. This will be an ONLINE ONLY session. To attend please use our recurring zoom link: https://uva-live.zoom.us/j/89230639823?pwd=YWJuSnJmTDhXcWhmd1ZkeG5zb0o5UT09 (Meeting ID: 892 3063 9823, Passcode: 421723) You can find the details of the talk below. Speaker: Emiliano Lorini Date and Time: Thursday, April 6th 2023, 16:30-18:00 Venue: ONLINE ONLY. (i.e. not hybrid!) Title: Non-Classical Logics for Explanations in AI Systems Abstract. I will show how non-classical logics with special emphasis on modal logic, epistemic logic, conditional logic and deontic logic can be used to represent and compare a rich variety of explanations in classifier systems widely used in the field machine learning including abductive, constrastive, counterfactual, objective vs subjective, interactive as well as concepts of bias, discrimination and protected feature. I will present proof-theoretic and complexity results for these logics and illustrate their expressiveness through some concrete examples. Hope to see you there! The LIRa team

1 0

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

ILLC-LIRa April 2023