David Rozado

David Rozado
  • computer science
  • Associate Professor at Otago Polytechnic

Associate Professor

About

62
Publications
24,698
Reads
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1,399
Citations
Current institution
Otago Polytechnic
Current position
  • Associate Professor

Publications

Publications (62)
Article
Full-text available
Recent advancements in Large Language Models (LLMs) suggest imminent commercial applications of such AI systems where they will serve as gateways to interact with technology and the accumulated body of human knowledge. The possibility of political biases embedded in these models raises concerns about their potential misusage. In this work, we repor...
Article
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This work describes a chronological (2000–2019) analysis of sentiment and emotion in 23 million headlines from 47 news media outlets popular in the United States. We use Transformer language models fine-tuned for detection of sentiment (positive, negative) and Ekman’s six basic emotions (anger, disgust, fear, joy, sadness, surprise) plus neutral to...
Article
Full-text available
This work analyzes the prevalence of words denoting prejudice in 27 million news and opinion articles written between 1970 and 2019 and published in 47 of the most popular news media outlets in the United States. Our results show that the frequency of words that denote specific prejudice types related to ethnicity, gender, sexual, and religious ori...
Article
Full-text available
Concerns about gender bias in word embedding models have captured substantial attention in the algorithmic bias research literature. Other bias types however have received lesser amounts of scrutiny. This work describes a large-scale analysis of sentiment associations in popular word embedding models along the lines of gender and ethnicity but also...
Article
Full-text available
I report here a comprehensive analysis about the political preferences embedded in Large Language Models (LLMs). Namely, I administer 11 political orientation tests, designed to identify the political preferences of the test taker, to 24 state-of-the-art conversational LLMs, both closed and open source. When probed with questions/statements with po...
Article
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Previous research has identified a post-2010 sharp increase of terms used to denounce prejudice (i.e. racism, sexism, homophobia, Islamophobia, anti-Semitism, etc.) in U.S. and U.K. news media content. Here, we extend previous analysis to an international sample of news media organizations. Thus, we quantify the prevalence of prejudice-denouncing t...
Preprint
Full-text available
Previous research has identified a post-2010 sharp increase of words used to denounce prejudice (i.e. racism, sexism, homophobia, Islamophobia, anti-Semitism, etc) in US and UK news media content. Some have referred to these institutional trends and related shifts in US public opinion about increasing perceptions of prejudice severity in society as...
Article
Full-text available
Few topics are currently as polarizing as the appropriate limits, and perceived dangers, of free speech on university campuses. A side effect of this polarized environment is that students themselves may be reluctant to speak publicly on politically sensitive topics. Indeed, recent surveys by the Heterodox Academy (HxA) revealed that a majority of...
Technical Report
Full-text available
• Recent years have seen considerable debate about the rise of political polarisation in British society. Specifically, over the last decade, various studies have suggested that the UK is now rapidly following the United States into a more polarised politics in which intensifying ‘culture wars’ over issues such as racism, identity, diversity, histo...
Article
Despite a marked decline in prejudicial attitudes among the public at large, a survey of 175 million scholarly articles published over the last five decades has found a sharp spike in words denoting prejudice and social justice themes beginning in 2010 and lasting at least through the first few months of 2020, a pattern observed within news media c...
Article
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This work describes an analysis of political associations in 27 million diachronic (1975–2019) news and opinion articles from 47 news media outlets popular in the United States. We use embedding models trained on individual outlets content to quantify outlet-specific latent associations between positive/negative sentiment words and terms loaded wit...
Article
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The term political extremism is commonly used to refer to political attitudes considered to be outside the ideological mainstream. This study leverages computational content analysis of big data to longitudinally examine (1970–2019) the prevalence of terms denoting far-right and far-left political extremism in more than 30 million written news and...
Article
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Previous scholarly literature has documented a pronounced increase in the prevalence of prejudice-denoting terms in American news media content. Some have referred to this shift in journalistic discourse and related public opinion trends signaling increasing perceptions of prejudice severity in U.S. society as The Great Awokening. This work analyze...
Article
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The COVID-19 pandemic has been one of the most disruptive and painful phenomena of the last few decades. As of July 2021, the origins of the SARS-CoV-2 virus that caused the outbreak remain a mystery. This work analyzes the prevalence in news media articles of two popular hypotheses about SARS-CoV-2 virus origins: the natural emergence and the lab-...
Article
This work examines word frequency usage in New York Times articles written between January 1, 1970 and December 31, 2018. Charting word frequencies in a diachronic corpus tracks the time course of historical events and highlights the dynamics of social trends within the cultural context where the texts were produced. My analysis focuses primarily o...
Article
Full-text available
Most citizens in modern liberal democracies regularly consume news media content to inform themselves about current affairs. Thus, content analysis of news and opinion articles from popular media outlets can provide rich insight about the cultural milieu where such textual artifacts originated. Combining computational tools for content analysis wit...
Article
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The term diversity can be operationalized demographically (in terms of physical or external characteristics such as race, gender, ethnicity and nationality) or intellectually (in terms of mental phenomena such as viewpoints, beliefs, ideas and political opinion). This work examines the context in which the concept of diversity is used by 50 US elit...
Preprint
Full-text available
Concerns about gender bias in word embedding models have captured substantial attention in the algorithmic bias research literature. Yet, the common elastic usage of the term bias to describe a broad array of distinct algorithmic phenomena can be misleading. Here, a large-scale analysis of gender associations in popular pre-trained word embedding m...
Chapter
Gaze reactive accessibility software for computer control permits individuals with moderate or severe dysfunction of motor function to operate a computer exclusively via gaze. Unfortunately, the small size of the severely motor impaired community and the large fixed costs of developing accessibility software results in commercial gaze control softw...
Article
Full-text available
The introduction of next-generation technologies to the maritime shipping industry, including Portable Pilotage Units, Remote Pilotage, advanced situation awareness aids, and Autonomous Shipping, creates an urgent need to understand operator workload during Bridge Team operations, and co-operations with shore based personnel. In this paper we analy...
Conference Paper
Accessibility software for motor impairment permits individuals who cannot access electronic devices through traditional input hardware to control desktop computers, tablets or smart phones despite moderate or severe dysfunction of motor control. Due to the relatively small size of the severely motor impaired community and the large fixed costs of...
Article
In this work, we show how our open source accessibility software, the FaceSwitch, can help motor-impaired subjects to efficiently interact with a computer hands-free. The FaceSwitch enhances gaze interaction with video-based face gestures interaction. The emerging multimodal system allows for interaction with a user interface by means of gaze point...
Article
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HCI systems that bypass manual control can be beneficial for many use cases, including users with severe motor disability. We investigated pupillometry (inferring mental activity via dilations of the pupil) as an interaction method because it is non-invasive, easy to analyse, and increasingly available for practical development. In 3 experiments we...
Conference Paper
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We introduce here the FaceSwitch, an accessibility software system designed to facilitate computer interaction for users who are challenged in the mobility of their upper limbs. The FaceSwitch software tracks landmark features in a user's face using a deformable face tracker. The system lets the user map specific facial gestures to customized compu...
Article
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Combining signals from traditional electroencephalography with those of novel physiological measures such as pupil dilation could enable more accurate and robust real-time monitoring of cognitive workload.
Article
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Non-contact measurements of cardiac pulse can provide robust measurement of heart rate (HR) without the annoyance of attaching electrodes to the body. In this paper we explore a novel and reliable method to carry out video-based HR estimation and propose various performance improvement over existing approaches. The investigated method uses Independ...
Article
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For individuals with high degrees of motor disability or locked-in syndrome, it is impractical or impossible to use mechanical switches to interact with electronic devices. Brain computer interfaces (BCIs) can use motor imagery to detect interaction intention from users but lack the accuracy of mechanical switches. Hence, there exists a strong need...
Article
Video-oculography gaze tracking permits the monitoring of a computer user's point of regard (PoR) on the screen by tracking with a video camera the center of the pupil and patterns of infrared reflections on the cornea. Gaze tracking has been used as an alternative to traditional pointing mechanisms during human computer interaction. Gaze direction...
Article
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We explore and test the suitability of four interfaces for tele-operation in Human-Robot Interaction. In a "pick-and-place" task, users select tar- gets and locations using eye-tracking (activated by either a mouse-click or by dwell time), a touchscreen, or a standard computer mouse. We validated our hypotheses in two user studies. Contrary to our...
Article
The emergence of small handheld devices such as tablets and smartphones, often with touch sensitive surfaces as their only input modality, has spurred a growing interest in the subject of gestures for human–computer interaction (HCI). It has been proven before that eye movements can be consciously controlled by humans to the extent of performing se...
Article
This work explores the combination of gaze and speech to interact with objects in the environment. A head-mounted wireless gaze tracker in the form of gaze tracking glasses is used for mobile monitoring of a subject's point of regard on the surrounding environment. In our proposed system, a mobile subject gazes at an object of interest in the envir...
Conference Paper
The performance of current speech recognition algorithms is well below that of human speech recognition, with high number of misrecognized words in quiet environments and degrading even further in noisy ones. Therefore, hands-free interaction remains a deeply frustrating experience. In this work, we present an innovative form of correcting misrecog...
Article
This work presents the development of a low cost Human-Robot gaze estimation system for the purpose of promoting joint Human-Robot workspaces in daily scenarios. We have developed this system using only monocular eye tracking and the 2D gaze point. Prior to this work there have been many efforts to bridge the gap between human and robots by develop...
Article
Gaze tracking has been suggested as an alternative to traditional computer pointing mechanisms. However, the accuracy limitations of gaze estimation algorithms and the fatigue imposed on users when overloading the visual perceptual channel with a motor control task have prevented the widespread adoption of gaze as a pointing modality. Rather than u...
Article
Predefined sequences of eye movements, or ‘gaze gestures’, can be consciously performed by humans and monitored non-invasively using remote video oculography. Gaze gestures hold great potential in human–computer interaction, HCI, as long as they can be easily assimilated by potential users, monitored using low cost gaze tracking equipment and machi...
Article
Sign language recognition, SLR, using spatial positions and arrangements of the hands over time is a challenging multi-variable time series recognition problem with several potential applications. Here we explore, for SLR purposes, a hierarchically connected network of nodes based on a Bayesian-like paradigm known as hierarchical temporal memory, H...
Article
Eye movements can be consciously controlled by humans to the extent of performing sequences of predefined movement patterns, or 'gaze gestures'. Gaze gestures can be tracked noninvasively employing a video-based eye tracking system. Gaze gestures hold the potential to become an emerging input paradigm in the context of human-computer interaction (H...
Conference Paper
Eye movements can be consciously controlled by humans to the extent of performing sequences of predefined movement patterns, or 'gaze gestures'. Gaze gestures can be tracked non-invasively employing a video-based eye tracking system. Gaze gestures hold great potential in the context of Human Computer Interaction as low-cost gaze trackers become mor...
Data
Eurexpress template generation and riboprobe synthesis workflow. (0.07 MB PDF)
Data
Full-text available
Comparison of expression patterns for E14.5 CNS-specific genes between embryonic and adult brain. This figure illustrates two examples of degrees of similarity between fetal and adult brain. (A and B) show partial concordance of the expression pattern of the RFamide-related peptide gene in neurons of the dorsomedial hypothalamic nucleus (DM) at E14...
Data
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Transcriptome complexity of main organs and anatomical structures. The bars represent the number of genes displaying a regional expression pattern in selected organs and structures. (0.03 MB PDF)
Data
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List of genes that display exclusive expression in selected structures. (0.10 MB PDF)
Data
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Comparison of expression patterns for E14.5 CNS-specific genes between embryonic and adult brain. This figure illustrates typical cases of equivalent (A–F), partially equivalent (G), and different (H) patterns. Images shown were downloaded from either the Eurexpress database or the ABA. 4V, fourth ventricle; bv, brain vasculature; cb, cerebellum; c...
Data
Screen view of the FIATAS annotation interface. The image displayed in the left-hand view can be expanded to full resolution and panned at will. The right-hand side image selector also shows which images are annotated. The upper, partially hidden dialog box shows the current “inbox” and which user is currently annotating which assay, and provides t...
Data
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Validation of Eurexpress data against published data. (0.21 MB DOC)
Data
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Distribution of genes with restricted spatial expression in different anatomical structures. (0.09 MB PDF)
Data
Supporting methods. This file gives an overview of the methods used in this manuscript. Additional supplementary data on clustering can be found at http://www.eurexpress.org/ee. (0.20 MB DOC)
Data
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Genoarchitecture of developing mouse forebrain Nissl-stained sagittal sections. Midline (A) and progressively more lateral sections (C and E) illustrating the basic anatomy, with the pertinent anatomical structures labeled. (B, D, and F) show the same planes as in (A, C, and E) with expression patterns of several genes indicated by color. Names of...
Data
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Tissue distribution at E14.5 of the murine homologs of three human disease genes. The human disease genes are SALL1, GDF5, and SLC26A2, responsible for Townes-Brocks syndrome, brachydactyly type C, and achondrogenesis type 1B, respectively. The expression observed is consistent with the phenotypic spectrum of the corresponding disease (see Table S7...
Data
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Eurexpress data management architecture. Each process on the outer pipeline is tracked by data exchange with the tracking database (TDB). The yellow arrows represent data flow using protocols as described in the test. (0.66 MB PDF)
Data
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Comparison of independently produced ISH data for the solute carrier superfamily. (0.53 MB PDF)
Data
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Evaluation in the adult mouse brain of the expression of the genes expressed exclusively in the CNS at E14.5. (0.34 MB PDF)
Data
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Comparison of Slc expression patterns between embryonic and adult mouse brain. (0.36 MB PDF)
Data
Expression of Wnt signaling components in the E14.5 embryo. (0.09 MB PDF)
Data
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List of murine homologs of human disease genes whose tissue distribution at E14.5 is consistent with the corresponding human disease phenotype. (0.08 MB PDF)
Data
Classification of single cell expression patterns in the E14.5 liver. (3.64 MB PDF)
Article
Full-text available
Ascertaining when and where genes are expressed is of crucial importance to understanding or predicting the physiological role of genes and proteins and how they interact to form the complex networks that underlie organ development and function. It is, therefore, crucial to determine on a genome-wide level, the spatio-temporal gene expression profi...
Conference Paper
Hierarchical Temporal Memory (HTM) is an emerging computational paradigm consisting of a hierarchically connected network of nodes. The hierarchy models a key design principle of neocortical organization. Nodes throughout the hierarchy encode information by means of clustering spatial instances within their receptive fields according to temporal pr...

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