Dear all,
We will have our next LIRa session on Thursday, November 5th. Our speaker is Mehrnoosh Sadrzadeh. You can find the details of the talk below. We will use our recurring zoom link: https://uva-live.zoom.us/j/92907704256?pwd=anY3WkFmQVhLZGhjT2JXMlhjQVl1dz09 (Meeting ID: 929 0770 4256, Passcode: 036024).
Date and Time: Thursday, November 5th 2020, 16:30-18:00,
Amsterdam time.
Venue: online.
Title: Linguistic Random Matrix Theory
Abstract.
Constructions in type-driven compositional distributional semantics
associate large collections of matrices of size D to linguistic
corpora. Following the work of Wigner and Dyson on developing random
matrix theory for analysing energy levels of nuclei using
distributions of matrices of random variables, we develop the proposal
of analysing the statistical characteristics of linguistic data in the
framework of permutation invariant matrices. The observables in this
framework are permutation invariant polynomial functions of the matrix
entries, which correspond to directed graphs. Using the general
13-parameter permutation invariant Gaussian matrix models recently
solved, we find, using a dataset of matrices constructed via standard
techniques in distributional semantics, that the expectation values of
a large class of cubic and quartic observables show high gaussianity
at levels between 90 to 99 percent. We find evidence that observables
with similar matrix model characteristics of gaussianity also have
high degrees of correlation between the ranked lists of words
associated to these observables. This is joint work with Ramgoolam and
Sword from String Theory in QMUL and with Kartsaklis from Apple.
Hope to see you there!
The LIRa team
Dear all,
We will have our next LIRa session tomorrow. We will use our recurring zoom link: https://uva-live.zoom.us/j/92907704256?pwd=anY3WkFmQVhLZGhjT2JXMlhjQVl1dz09 (Meeting ID: 929 0770 4256, Passcode: 036024).
Date and Time: Thursday, October 29th 2020, 16:30-18:00,
Amsterdam time.
Venue: online.
Title: Semiring Provenance for Logic and Games
Abstract.
Semiring provenance is a successful approach, originating in database
theory, to providing detailed information on how atomic facts in a
given finite structure combine to yield the truth or falsity of a
logical statement. In particular, general provenance semirings of
polynomials or formal power series provide precise descriptions of the
evaluation strategies or \"proof trees\'\' for the statement. By
evaluating these descriptions in specific application semirings, one
can extract practical information for instance about the confidence
that we assign to a statement or about the cost of its evaluation.
While semiring provenance, as developed in database theory, has mainly
been confined to positive query languages, such as (unions of)
conjunctive queries, positive relational algebra, or datalog, we
generalize this approach to logics that include negation, such as full
first-order logic or least fixed-point logic, exploiting connections
between logic and games. Specific mathematical challenges arise from
the interleaving of negation and fixed-point inductions, which lead us
to the study of fully continuous absorptive semirings and to
generalized absorptive polynomials.
Beyond the applications to the evaluation of database query and
logical sentences, semiring provenance also has interesting
interpretations in finite and infinite games. Semiring evaluations
permit to answer more subtle questions than just who wins the game,
such the number or costs of winning strategies, or issues such as
confidence and cost in game-theoretic settings.
Hope to see you there!
The LIRa team
Dear all,
We will have our next LIRa session on Thursday, October 29th. Our speaker is Erich Grädel. You can find the details of the talk below. We will use our recurring zoom link: https://uva-live.zoom.us/j/92907704256?pwd=anY3WkFmQVhLZGhjT2JXMlhjQVl1dz09 (Meeting ID: 929 0770 4256, Passcode: 036024).
Date and Time: Thursday, October 29th 2020, 16:30-18:00,
Amsterdam time.
Venue: online.
Title: Semiring Provenance for Logic and Games
Abstract.
Semiring provenance is a successful approach, originating in database
theory, to providing detailed information on how atomic facts in a
given finite structure combine to yield the truth or falsity of a
logical statement. In particular, general provenance semirings of
polynomials or formal power series provide precise descriptions of the
evaluation strategies or \"proof trees\'\' for the statement. By
evaluating these descriptions in specific application semirings, one
can extract practical information for instance about the confidence
that we assign to a statement or about the cost of its evaluation.
While semiring provenance, as developed in database theory, has mainly
been confined to positive query languages, such as (unions of)
conjunctive queries, positive relational algebra, or datalog, we
generalize this approach to logics that include negation, such as full
first-order logic or least fixed-point logic, exploiting connections
between logic and games. Specific mathematical challenges arise from
the interleaving of negation and fixed-point inductions, which lead us
to the study of fully continuous absorptive semirings and to
generalized absorptive polynomials.
Beyond the applications to the evaluation of database query and
logical sentences, semiring provenance also has interesting
interpretations in finite and infinite games. Semiring evaluations
permit to answer more subtle questions than just who wins the game,
such the number or costs of winning strategies, or issues such as
confidence and cost in game-theoretic settings.
.
Hope to see you there!
The LIRa team
Dear all,
We will have our next LIRa session tomorrow. We will use our recurring zoom link: https://uva-live.zoom.us/j/92907704256?pwd=anY3WkFmQVhLZGhjT2JXMlhjQVl1dz09 (Meeting ID: 929 0770 4256, Passcode: 036024).
Speaker: Roberto Giuntini
Date and Time: Thursday, October 22nd 2020, 16:30-18:00,
Amsterdam time.
Venue: online.
Title: A quantum-like approach to Machine Learning
Abstract.
In this talk we propose a new quantum-like method for the binary
classification applied to classical datasets. Inspired by the quantum
Helstrom measurement, this approach allows one to define a new
classifier, called Helstrom Quantum Classifier (HQC). This binary
classifier (inspired by the concept of distinguishability between
quantum states) acts on density matrices—called density
patterns—that are the quantum encoding of classical patterns of a
dataset. Different forms of quantum encodings will be presented and
compared. We will then contrast the performance of HQC with that of a
highly representative set of classical classifiers with respect to
different classes of datasets. The experimental results show that HQC
is very flexible and outperforms the other classifiers with respect to
many (artificial and real-world) datasets. Finally, we will show that
the performance of our classifier is positively correlated to the
increase in the number of “quantum copies” of a pattern and the
resulting tensor product thereof.
Hope to see you there!
The LIRa team
Dear all,
We will have our next LIRa session on Thursday, October 22nd. Our speaker is Roberto Giuntini. You can find the details of the talk below. We will use our recurring zoom link: https://uva-live.zoom.us/j/92907704256?pwd=anY3WkFmQVhLZGhjT2JXMlhjQVl1dz09 (Meeting ID: 929 0770 4256, Passcode: 036024).
Speaker: Roberto Giuntini
Date and Time: Thursday, October 22nd 2020, 16:30-18:00,
Amsterdam time.
Venue: online.
Title: A quantum-like approach to Machine Learning
Abstract.
In this talk we propose a new quantum-like method for the binary
classification applied to classical datasets. Inspired by the quantum
Helstrom measurement, this approach allows one to define a new
classifier, called Helstrom Quantum Classifier (HQC). This binary
classifier (inspired by the concept of distinguishability between
quantum states) acts on density matrices—called density
patterns—that are the quantum encoding of classical patterns of a
dataset. Different forms of quantum encodings will be presented and
compared. We will then contrast the performance of HQC with that of a
highly representative set of classical classifiers with respect to
different classes of datasets. The experimental results show that HQC
is very flexible and outperforms the other classifiers with respect to
many (artificial and real-world) datasets. Finally, we will show that
the performance of our classifier is positively correlated to the
increase in the number of “quantum copies” of a pattern and the
resulting tensor product thereof.
Hope to see you there!
The LIRa team
Dear all,
We will have our next LIRa session tomorrow. We will use our recurring zoom link: https://uva-live.zoom.us/j/92907704256?pwd=anY3WkFmQVhLZGhjT2JXMlhjQVl1dz09 (Meeting ID: 929 0770 4256, Passcode: 036024).
Speaker: Eric Pacuit
Date and Time: Thursday, October 15th 2020, 16:30-18:00,
Amsterdam time.
Venue: online.
Title: Axioms for defeat in variable-candidate and variable-voter
elections
Abstract.
This talk will discuss axioms concerning when one candidate should
defeat another in a democratic election involving two or more
candidates. In a recent paper, we proposed a weakening of Kenneth
Arrow\'s famous condition of the Independence of Irrelevant
Alternatives (IIA), called Coherent IIA. We showed that five
well-known axioms of voting plus Coherent IIA single out a voting
procedure studied in other recent work called Split Cycle. The main
objective of this talk is to explain how Split Cycle escapes Arrow\'s
Impossibility Theorem and related impossibility results. This work is
part of a larger project focused on identifying voting methods that
respond reasonably to the addition of new candidates and new voters to
an election: If a voting method selects candidate $x$ as a winner,
then $x$ should not become a loser by the addition of a new candidate
to whom $x$ is majority preferred or the addition of a new voter who
ranks $x$ in first place. We are interested both in characterizing
voting methods that satisfy this and related principles and using
computer simulations to assess the frequency and severity of
violations to this principle for different voting methods.
This is joint work with Wes Holliday.
.
Hope to see you there!
The LIRa team
Dear all,
We will have our next LIRa session on Thursday, October 15th. Our speaker is Eric Pacuit. You can find the details of the talk below. We will use our recurring zoom link: https://uva-live.zoom.us/j/92907704256?pwd=anY3WkFmQVhLZGhjT2JXMlhjQVl1dz09 (Meeting ID: 929 0770 4256, Passcode: 036024).
Speaker: Eric Pacuit
Date and Time: Thursday, October 15th 2020, 16:30-18:00, Amsterdam time.
Venue: online.
Title: Axioms for defeat in variable-candidate and variable-voter elections
Abstract.
This talk will discuss axioms concerning when one candidate should defeat another in a democratic election involving two or more candidates. In a recent paper, we proposed a weakening of Kenneth Arrow’s famous condition of the Independence of Irrelevant Alternatives (IIA), called Coherent IIA. We showed that five well-known axioms of voting plus Coherent IIA single out a voting procedure studied in other recent work called Split Cycle. The main objective of this talk is to explain how Split Cycle escapes Arrow’s Impossibility Theorem and related impossibility results. This work is part of a larger project focused on identifying voting methods that respond reasonably to the addition of new candidates and new voters to an election: If a voting method selects candidate $x$ as a winner, then $x$ should not become a loser by the addition of a new candidate to whom $x$ is majority preferred or the addition of a new voter who ranks $x$ in first place. We are interested both in characterizing voting methods that satisfy this and related principles and using computer simulations to assess the frequency and severity of violations to this principle for different voting methods.
This is joint work with Wes Holliday.
Hope to see you there!
The LIRa team
Dear all,
The 3rd International Workshop on Dynamic Logic: New Trends and Applications (DaLí 2020) will take place on 9-10 October. You can find more about the workshop here: http://www.cs.cas.cz/dali2020/
The zoom details are below (do not circulate without consulting the organizers)
Time (Day 1): Oct 9, 2020 09:20 AM Prague Bratislava
Time (Day 2): Oct 10, 2020 09:30 AM Prague Bratislava
Join Zoom Meeting
https://cesnet.zoom.us/j/94567852173?pwd=WmxlZkJJcHhQZmk1Rko5a3dPK1FsQT09
Meeting ID: 945 6785 2173
Passcode: 572820
Hope to see you there!
The LIRa team
Dear all,
Unfortunately, our next speaker, Mehrnoosh Sadrzadeh, had to postpone her talk, so there will be no LIRa session this coming Thursday, October 8.
We would like to remind you that we still have a LIRa related event this week: the 3rd International Workshop on Dynamic Logic (DaLi 2020) will be hold as an online workshop on Friday and Saturday. For more information please visit the workshop webpage at the following link: http://www.cs.cas.cz/dali2020/.
Hope to see you there!
The LIRa team