Investigating the relationship between language model perplexity and IR precision-recall measures

An empirical study has been conducted investigating the relationship between the performance of an aspect based language model in terms of perplexity and the corresponding information retrieval performance obtained. It is observed, on the corpora considered, that the perplexity of the language model has a systematic relationship with the achievable precision recall performance though it is not statistically significant

Simulating the sensitivity of cell nutritive environment to composition changes within the intervertebral disc

Altered nutrition in the intervertebral disc affects cell viability and can generate catabolic cascades contributing to extracellular matrix (ECM) degradation. Such degradation is expected to affect couplings between disc mechanics and nutrition, contributing to accelerate degenerative processes. However, the relation of ECM changes to major biophysical events within the loaded disc remains unclear. A L4-L5 disc finite element model including the nucleus (NP), annulus (AF) and endplates was used and coupled to a transport-cell viability model. Solute concentrations and cell viability were evaluated along the mid-sagittal plane path. A design of experiment (DOE) was performed. DOE parameters corresponded to AF and NP biochemical tissue measurements in discs with different degeneration grades. Cell viability was not affected by any parameter combinations defined. Nonetheless, the initial water content was the parameter that affected the most the solute contents, especially glucose. Calculations showed that altered NP composition could negatively affect AF cell nutrition. Results suggested that AF and NP tissue degeneration are not critical to nutrition-related cell viability at early-stage of disc degeneration. However, small ECM degenerative changes may alter significantly disc nutrition under mechanical loads. Coupling disc mechano-transport simulations and enzyme expression studies could allow identifying spatiotemporal sequences related to tissue catabolism

Looking at Vector Space and Language Models for IR using Density Matrices

In this work, we conduct a joint analysis of both Vector Space and Language Models for IR using the mathematical framework of Quantum Theory. We shed light on how both models allocate the space of density matrices. A density matrix is shown to be a general representational tool capable of leveraging capabilities of both VSM and LM representations thus paving the way for a new generation of retrieval models. We analyze the possible implications suggested by our findings.Comment: In Proceedings of Quantum Interaction 201

Gaze direction when driving after dark on main and residential roads: Where is the dominant location?

CIE JTC-1 has requested data regarding the size and shape of the distribution of drivers’ eye movement in order to characterise their visual adaptation. This article reports the eye movement of drivers along two routes in Berlin after dark, a main road and a residential street, captured using eye tracking. It was found that viewing behaviour differed between the two types of road. On the main road eye movement was clustered within a circle of approximately 10° diameter, centred at the horizon of the lane. On the residential street eye movement is clustered slightly (3.8°) towards the near side; eye movements were best captured with either an ellipse of approximate axes 10° vertical and 20° horizontal, centred on the lane ahead, or a 10° circle centred 3.8° towards the near side. These distributions reflect a driver’s tendency to look towards locations of anticipated hazards

Meaning-focused and Quantum-inspired Information Retrieval

In recent years, quantum-based methods have promisingly integrated the traditional procedures in information retrieval (IR) and natural language processing (NLP). Inspired by our research on the identification and application of quantum structures in cognition, more specifically our work on the representation of concepts and their combinations, we put forward a 'quantum meaning based' framework for structured query retrieval in text corpora and standardized testing corpora. This scheme for IR rests on considering as basic notions, (i) 'entities of meaning', e.g., concepts and their combinations and (ii) traces of such entities of meaning, which is how documents are considered in this approach. The meaning content of these 'entities of meaning' is reconstructed by solving an 'inverse problem' in the quantum formalism, consisting of reconstructing the full states of the entities of meaning from their collapsed states identified as traces in relevant documents. The advantages with respect to traditional approaches, such as Latent Semantic Analysis (LSA), are discussed by means of concrete examples.Comment: 11 page

Semantic distillation: a method for clustering objects by their contextual specificity

Techniques for data-mining, latent semantic analysis, contextual search of databases, etc. have long ago been developed by computer scientists working on information retrieval (IR). Experimental scientists, from all disciplines, having to analyse large collections of raw experimental data (astronomical, physical, biological, etc.) have developed powerful methods for their statistical analysis and for clustering, categorising, and classifying objects. Finally, physicists have developed a theory of quantum measurement, unifying the logical, algebraic, and probabilistic aspects of queries into a single formalism. The purpose of this paper is twofold: first to show that when formulated at an abstract level, problems from IR, from statistical data analysis, and from physical measurement theories are very similar and hence can profitably be cross-fertilised, and, secondly, to propose a novel method of fuzzy hierarchical clustering, termed \textit{semantic distillation} -- strongly inspired from the theory of quantum measurement --, we developed to analyse raw data coming from various types of experiments on DNA arrays. We illustrate the method by analysing DNA arrays experiments and clustering the genes of the array according to their specificity.Comment: Accepted for publication in Studies in Computational Intelligence, Springer-Verla

A cognitive remediation training for young adults with psychotic disorders to support their participation in education - study protocol for a pilot randomized controlled trial

Background: Most severe mental disorders have their onset between the age of 17 and 27, a time when many young adults begin participating in secondary or post-secondary education. The cognitive deficits typically associated with psychiatric disorders, especially psychotic disorders, increase the risk of leaving school early, which can lead to a reduction in employment opportunities later on in life and, in turn, a poorer long-term prognosis. Therefore, specific interventions aiming to improve these cognitive functions are needed. Cognitive remediation (CR) aims to improve cognitive functioning and may increase real-world functioning in educational performance. This study aims to examine the feasibility and applicability of a CR training named Mindset for students with psychotic disorders in the Netherlands. Methods/design: Sixty students diagnosed with a psychotic disorder and currently reporting cognitive deficits will be included from four Dutch Mental Health Care institutes. Half of the participants (N = 30) will be randomly assigned to the CR training consisting of twelve, individual, weekly 1-h meetings. The other half will be assigned to an active control condition consisting of twelve weekly assignments that will be sent by email aiming to improve school performance. Students will be evaluated at baseline (T0), directly after finishing the CR training or control intervention (T1), and 6 months later (T2). Treatment feasibility will be the primary outcome, using evaluation forms, interviews with trainers and participants, number of study drop outs, and patient eligibility and recruitment rates. School functioning, cognitive functioning, and strategy use will also be assessed to get a preliminary idea of the potential effectiveness of the intervention. Discussion: The CR training in this study will provide real-world examples and exercises aimed to teach useful strategies to cope with the cognitive deficits experienced by students with psychotic disorders. Furthermore, since students with other psychiatric disorders might also experience cognitive deficits, the results of this study may also provide some further implications for future studies on the effect of this CR training for students with these disorders. Trial registration: The study was registered with Trialregister.nl, no. NL6590 (NTR6764), date registered: September 7, 2017. Register name: Mindset. A cognitive rehabilitation training for young adults with psychotic spectrum disorder in an educational setting: A pilot study.Protocol version: 3, date December 23, 2019