30 research outputs found
Supplemental Material - The Influence of Agent Transparency and Complexity on Situation Awareness, Mental Workload, and Task Performance
No full textSupplemental Material for The Influence of Agent Transparency and Complexity on Situation Awareness, Mental Workload, and Task Performance by Koen van de Merwe, Steven Mallam, Salman Nazir, and Øystein Engelhardtsen in Journal of Cognitive Engineering and Decision Making</p
sj-pdf-1-hfs-10.1177_00187208221077804 - Supplemental Material for Agent Transparency, Situation Awareness, Mental Workload, and Operator Performance: A Systematic Literature Review
No full textSupplemental Material, sj-pdf-1-hfs-10.1177_00187208221077804 for Agent Transparency, Situation Awareness, Mental Workload, and Operator Performance: A Systematic Literature Review by Koen van de Merwe, Steven Mallam, and Salman Nazir in Human Factors</p
Agent Transparency and Human Performance in Supervisory Control
No full textBackground: In future maritime transport, Artificial Intelligence (AI)-enabled systems may allow ships to sail without direct human involvement. Here, humans are foreseen to take a supervisory role to ensure performance and safety requirements are met. However, there are well-known challenges related to this role that may affect the operator’s ability to intervene. Agent transparency is a design principle aimed at supporting supervisory control by providing humans with insight into the system’s decisions, planned actions, and internal reasoning. However, considering the novelty of the application of AI-enabled systems in safety-critical domains, there is limited experience with the effect of transparency on human supervisory performance in these settings.
Aim: The research aim is to explore the application of transparency to support supervisory control. Five research questions are investigated: 1. What is the relationship between agent transparency and Situation Awareness, mental workload, and task performance? 2. How is human performance achieved in conventional- and supervised maritime collision avoidance? 3. How does a model for human information processing form the basis for agent transparency in the ship autonomy context? 4. How should a maritime collision avoidance system be made transparent to a human supervisor? 5. What is the relationship between agent transparency and Situation Awareness, mental workload, and task performance in maritime autonomous collision avoidance manoeuvring?
Method: The study applied a mix of quantitative and qualitative methods: 1. Systematic literature review (review of 17 peer-reviewed articles) 2. Goal-Directed Task Analysis (in situ observations & interviews, 11 navigators, COLREGs) 3. Modelling (adapted and contextualized a model for human information processing) 4. Human Machine Interface development (iterative design process, workshops, 5 navigators) 5. Controlled experiment (measuring human performance effects, 34 navigators)
Results: The thesis outlined the following contributions: 1. Synthesis of the research state-of-the-art on agent transparency and human performance 2. Explored cognitive tasks, identified information requirements to support supervisory control 3. Established transparency model, created layers of information indicating system reasoning 4. Developed realistic traffic situations, applied transparency model to design interface concepts 5. Evaluated the model in the autonomous collision avoidance context, found effects on SA and task performance, but not on mental workload
Conclusions: This dissertation advocates the relevance of affording human operators with insight into the reasoning of autonomous systems and establishes transparency as an important prerequisite on the path towards safe and effective human-supervisory control. With these new insights, meaningful human work may be created where the combined capabilities of human-agent teams can be optimisedpublishedVersio
Classifying yield spread movements in sparse data through triplots
No full textThesis (PhD)--Stellenbosch University, 2020.ENGLISH SUMMARY : In many developing countries, including South Africa, all data that are required to
calculate the fair values of financial instruments are not always readily available.
Additionally, in some instances, companies who do not have the necessary quantitative
skills are reluctant to incorporate the correct fair valuation by failing to employ
the appropriate techniques. This problem is most notable with regards to unlisted
debt instruments.
There are two main inputs with regards to the valuation of unlisted debt instruments,
namely the the risk-free curve and the the yield spread. Investigation into
these two components forms the basis of this thesis. Firstly, an analysis is carried
out to derive approximations of risk-free curves in areas where data is sparse.
Thereafter it is investigated whether there is sufficient evidence of a significant
change in yield spreads of unlisted debt instruments. In order to determine these
changes, however, a new method that allows for simultaneous visualisation and
classification of data was developed - termed triplot classification with polybags.
This new classification technique also has the ability to limit misclassification rates. In the first paper, a proxy for the extended zero curve, calculated from other observable
inputs, is found through a simulation approach by incorporating two new techniques,
namely permuted integer multiple linear regression and aggregate standardised
model scoring. It was found that a Nelson Siegel fit, with a mixture of one
year forward rates as proxies for the long term zero point, and some discarding
of initial data points, performs relatively well in the training and testing data sets.
This new method allows for the approximation of risk-free curves where no long
term points are available, and further allows for the determinants of the yield curve
shape by considering other available data. The changes in these shape determining
parameters are used in the final paper as determinants for changes in yield
spreads.
For the second paper, a new classification technique is developed that was used in
the final paper. Classification techniques do not easily allow for visual interpretation,
nor do they usually allow for the limitation of the false negative and positive error rates. For some areas of research and practical applications these shortcomings
are important to address. In this paper, classification techniques are combined
with biplots, allowing for simultaneous visual representation and classification of
the data, resulting in the so-called triplot. By further incorporating polybags, the
ability of limiting misclassification type errors is also introduced. A simulation study
as well as an application is provided showing that the method provides similar results
compared to existing methods, but with added visualisation benefits. The paper
focuses purely on developing a statistical technique that can be applied to any field.
The application that is provided, for example, is on a medical data set. In the final
paper the technique is applied to changes in yield spreads.
The third paper considered changes in yield spreads which were analysed through
various covariates to determine whether significant decreases or increases would
have been observed for unlisted debt instruments. The methodology does not specifically
determine the new spread, but gives evidence on whether the initial implied
spread could be left the same, or whether a new spread should be determined.
These yield spread movements are classified using various share, interest rate, financial
ratio, and economic type covariates in a visually interpretive manner. This
also allows for a better understanding of how various factors drive the changes in
yield spreads. Finally, as supplement to each paper, a web-based application was built allowing
the reader to interact with all the data and properties of the methodologies discussed.
The following links can be used to access these three applications:
- Paper 1: https://carelvdmerwe.shinyapps.io/ProxyCurve/
- Paper 2: https://carelvdmerwe.shinyapps.io/TriplotSimulation/
- Paper 3: https://carelvdmerwe.shinyapps.io/SpreadsTriplot/AFRIKAANSE OPSOMMING : In baie ontwikkelende lande, insluitend Suid-Afrika, is al die inligting wat benodig
word om die billike waardes van finansiële instrumente te bereken, nie altyd geredelik
beskikbaar nie. In sommige gevalle is ondernemings, wat nie oor die nodige
kwantitatiewe vaardighede beskik nie, teësinnig om die regte billike waardasie te
bereken deur nie-toepaslike tegnieke te gebruik. Hierdie probleem is veral opvallend
ten opsigte van ongenoteerde skuldinstrumente.
Daar is twee hoof insette met betrekking tot die waardasie van ongenoteerde skuldinstrumente,
naamlik die risiko-vrye kromme en die opbrengskoersspreiding. Die
ondersoek na hierdie twee komponente vorm die basis van hierdie tesis. Eerstens
word ’n analise uitgevoer om benaderings vir die risiko-vrye kurwes af te lei in areas
waar die data skaars is. Daarna word ondersoek gedoen om vas te stel of daar voldoende
bewyse is van betekenisvolle veranderinge in die opbrengskoersspreiding
van ongenoteerde skuldinstrumente. Ten einde hierdie veranderinge te bepaal, is
’n nuwe metode wat gelyktydige visualisering en klassifikasie van data moontlik
maak, ontwikkel - genaamd tri-stipping-klassifisering met poli-sakke. Hierdie nuwe
klassifikasietegniek het ook die vermoë om wanklassifikasiekoerse te beperk. In die eerste artikel word ’n benadering vir die uitgebreide nul-kromme bereken uit
ander waarneembare insette. Dit word gevind deur middel van ’n simulasiebenadering
deur twee nuwe tegnieke, naamlik gepermuteerde heelgetal meervoudige
liniêre regressie en totale gestandaardiseerde model-telling, te gebruik. Dit is gevind
dat ’n Nelson Siegel-passing, met ’n kombinasie van een jaar vooruitkoerse as
benaderings vir die langtermyn nulpunt, en ’n mate van weglating van die aanvanklike
datapunte, relatief goed in die leer en toetsing van datastelle presteer. Hierdie
nuwe metode maak voorsiening vir die benadering van risiko-vrye krommes waar
geen langtermynpunte beskikbaar is nie. Dit maak ook voorsiening vir die komponente
van die opbrengskrommevorm deur ander beskikbare data in ag te neem.
Die veranderinge in hierdie vormbepalingsparameters word in die finale artikel as
komponente vir veranderinge in opbrengskoersspreidings gebruik. In die tweede artikel word ’n nuwe klassifikasietegniek ontwikkel wat in die finale
artikel gebruik word. Klassifikasietegnieke laat nie maklik visuele interpretasie toe
nie, en maak gewoonlik ook nie die beperking van die vals negatiewe en positiewe
foutkoerse moontlik nie. Hierdie tekortkominge is belangrik vir sommige
navorsings- en praktiese toepassingsareas. In hierdie artikel word klassifikasietegnieke
gekombineer met bi-stippings, waardeur die data gelyktydig visueel voorgestel
en geklassifiseer word, wat die sogenaamde tri-stipping tot gevolg het. Deur
poli-sakke in te bring, word die vermoë om foute in die wanklassifikasie te beperk
geïnkorporeer. ’n Simulasie-studie sowel as ’n toepassing word word geïllustreer.
Dit toon aan dat die metode soortgelyke resultate lewer in vergelyking met die bestaande
metodes, maar met ekstra visualiseringsvoordele. Die artikel fokus slegs
op die ontwikkeling van ’n statistiese tegniek wat op enige veld toegepas kan word.
Die toepassing wat byvoorbeeld verskaf is, was op ’n mediese datastel. In die finale
artikel word die tegniek op veranderinge in opbrengskoersspreidings toegepas. In die derde artikel word veranderinge in opbrengskoersspreidings ondersoek en
word dit deur middel van verskillende ko-variate ontleed om te bepaal of betekenisvolle
daling of stygings by ongenoteerde skuldinstrumente waargeneem word.
Die metodologie bepaal nie die nuwe spreiding spesifiek nie, maar lewer ’n bewys
of die aanvanklike geïmpliseerde spreiding dieselfde gelaat kan word, of dat
’n nuwe spreiding bepaal moet word. Hierdie opbrengskoersspreidingbewegings
word op ’n visueel interpretatiewe wyse geklassifiseer met behulp van verskillende
aandeel-, rentekoers-, finansiële verhouding- en ekonomiese tipe ko-variate. Dit
gee ook ’n beter begrip van hoe verskillende faktore die veranderinge in opbrengskoerse
beïnvloed.
Ten slotte, aanvullend tot elke artikel, is ’n webtoepassing gebou wat die leser in
staat stel om met al die data en eienskappe van die metodologieë wat bespreek is,
te eksperimenteer. Die volgende skakels kan gebruik word om toegang tot hierdie
drie toepassings te verkry:
- Artikel 1: https://carelvdmerwe.shinyapps.io/ProxyCurve/
- Artikel 2: https://carelvdmerwe.shinyapps.io/TriplotSimulation/
- Artikel 3: https://carelvdmerwe.shinyapps.io/SpreadsTriplot/Doctora
Die Stroom-op: April 1981
No full textThe Stroom-op is the official newspaper of Afrikaanse Hoër Seunskool and Afrikaanse Hoër Meisieskool Pretoria. The publication is a joint effort, each school doing its own part. It consist of 16 pages, each school writing 8 pages. / Die Stroom-op is die offisiële koerant van die Afrikaanse Hoër Seunskool en Afrikaanse Hoër Meisieskool Pretoria. Hierdie publikasie is 'n gesamentlike poging waar elke skool sy eie deel byvoeg. Dit bestaan uit 16 bladsye, waarvan 8 bladsye toegeken word aan elke skool
A Coherent Impression of the Pilots' Situation Awareness: Studying Relevant Human Factors Tools
No full textSituational Awareness Assessment in Flight Simulator Experiment
No full textWithin the HILAS (Human Integration into the Lifecycle of Aviation Systems) project a flight simulator experiment was performed. The aim of the experiment was to study and select relevant Human Factors tools for pilot Situational Awareness assessment. One specific scenario was designed in which a malfunction of the aircraft was simulated: an Indicated Air Speed discrepancy. The malfunction was introduced during flight and slowly progressed over time while researchers monitored if and how pilots detected the discrepancy. Pilot behaviour was studied during the scenario; i.e. pilots’ Situational Awareness was assessed via eye trackers and rating scales
Biological Psychiatry Congress 2015
No full textList of Abstract Titles and authors:
1. Psychosis: A matter of mental effort?
M Borg, Y Y van der Zee, J H Hsieh, H Temmingh, D J Stein, F M Howells
2.In search of an affordable, effective post-discharge intervention: A randomised control trial assessing the influence of a telephone-based intervention on readmissions for patients with severe mental illness in a developing country
U A Botha, L Koen, M Mazinu, E Jordaan, D J H Niehaus
3. The effect of early abstinence from long-term methamphetamine use on brain metabolism using 1H-magnetic resonance spectro-scopy (1H-MRS)
A Burger, S Brooks, D J Stein, F M Howells
4. The effect of in utero exposure to methamphetamine on brain metabolism in childhood using 1H-magnetic resonance spectroscopy (1H-MRS)
A Burger, A Roos, M Kwiatkowski, D J Stein, K A Donald, F M Howells
5. A prospective study of clinical, biological and functional aspects of outcome in first-episode psychosis: The EONKCS Study
B Chiliza, L Asmal, R Emsley
6. Stimulants as cognitive enhancers - perceptions v. evidence in a very real world
H M Clark
7. Pharmacogenomics in antipsychotic drugs
Ilse du Plessis
8. Serotonin in anxiety disorders and beyond
Ilse du Plessis
9. HIV infection results in ventral-striatal reward system hypo-activation during cue processing
S du Plessis, M Vink, J A Joska, E Koutsilieri, A Bagadia, D J Stein, R Emsley
10. Disease progression in schizophrenia: Is the illness or the treatment to blame?
R Emsley, M J Sian
11. Serotonin transporter variants play a role in anxiety sensitivity in South African adolescents
S M J Hemmings, L I Martin, L van der Merwe, R Benecke, K Domschke, S Seedat
12. Iron deficiency in two children diagnosed with multiple sclerosis: Report on whole exom sequencing
S Janse van Rensburg, R van Toorn, J F Schoeman, A Peeters, L R Fisher, K Moremi, M J Kotze
13. Benzodiazepines: Practical pharmacokinetics
P Joubert
14. What to consider when prescribing psychotropic medications
G Lippi
15. Current prescribing practices for obsessive-compulsive disorder in South Africa: Controversies and consensus
C Lochner, L Taljaard, D J Stein
16. Correlates of emotional and behavioural problems in children with preinatally acquired HIV in Cape Town, South Africa
K-A Louw, N Phillips, JIpser, J Hoare
17. The role of non-coding RNAs in fear extinction
S Malan-Muller, L Fairbairn, W M U Daniels, M J S Dashti, E J Oakleley, M Altorfer, J Harvey, S Seedat, J Gamieldien, S M J Hemmings
18. An analysis of the management og HIV-mental illness comorbidity at the psychiatric unit of the Dr George Mukhari Academic Hospital
M L Maodi, S T Rataemane, T Kyaw
19. The identification of novel genes in anxiety disorders: A gene X environment correlation and interaction study
N W McGregor, J Dimatelis, S M J Hemmings, C J Kinnear, D J Stein, V Russel, C Lochner
20. Collaborations between conventional medicine and traditional healers: Obstacles and possibilities
G Nortje, S Seedat, O Gureje
21. Thought disorder and form perception: Relationships with symptoms and cognitive function in first-episode schizophrenia
M R Olivier, R Emsley
22. Investigating the functional significance of genome-wide variants associated with antipsychotic treatment response
E Ovenden, B Drogemoller, L van der Merwe, R Emsley, L Warnich
23. The moral and bioethical determinants of "futility" in psychiatry
W P Pienaar
24. Single voxel proton magnetic resonance spectroscopy (1H-MRS) and volumetry of the amylgdala in social anxiety disorder in the context of early developmental trauma
D Rosenstein, A T Hess, J Zwart, F Ahmed-Leitao, E Meintjies, S Seedat
25. Schizoaffective disorder in an acute psychiatric unit: Profile of users and agreement with Operational Criteria (OPCRIT)
R R Singh, U Subramaney
26. The right to privacy and confidentiality: The ethics of expert diagnosis in the public media and the Oscar Pistorius trial
C Smith
27. A birth cohort study in South Africa: A psychiatric perspective
D J Stein
28. 'Womb Raiders': Women referred for observation in terms of the Criminal Procedures Act (CPA) charged with fetal abduction and murder
U Subramaney
29. Psycho-pharmacology of sleep wake disorders: An update
R Sykes
30. Refugee post-settlement in South Africa: Role of adjustment challenges and family in mental health outcomes
L Thela, A Tomita, V Maharaj, M Mhlongo, K Jonathan
31. Dstinguishing ADHD symptoms in psychotic disorders: A new insight in the adult ADHD questionnaire
Y van der Zee, M Borg, J H Hsieh, H Temmingh, D J Stein, F M Howells
32. Oscar Pistorius ethical dilemmas in a trial by media: Does this include psychiatric evaluation by media?
M Vorster
33. Genetic investigation of apetite aggression in South African former young offenders: The involvement of serotonin transporter gene
K Xulu, J Somer, M Hinsberger, R Weierstall, T Elbert, S Seedat, S Hemmings
34. Effects of HIV and childhood trauma on brain morphemtry and neurocognitive function
G Spies, F Ahmed-Leitao, C Fennema-Notestine, M Cherner, S Seedat
35. Measuring intentional behaviour normative data of a newly developed motor task battery
S Bakelaar, J Blampain, S Seedat, J van Hoof, Y Delevoye-Turrel
36. Resilience in social anxiety disorder and post-traumatic stress disorder in the context of childhood trauma
M Bship, S Bakelaar, D Rosenstein, S Seedat
37. The ethical dilemma of seclusion practices in psychiatry
G Chiba, U Subramaney
38. Physical activity and neurological soft signs in patients with schizophrenia
O Esan, C Osunbote, I Oladele, S Fakunle, C Ehindero
39. A retrospective study of completed suicides in the Nelson Mandela Bay Metropolitan Area from 2008 to 2013 - preliminary results
C Grobler, J Strumpher, R Jacobs
40. Serotonin transporter variants play a role in anxiety sensitivity in South African adolescents
S M J Hemmings, L I Martin, L van der Merwe, R Benecke, K Domschke, S Seedat
41. Investigation of variants within antipsychotic candidate pharmacogenes associated with treatment outcome
F Higgins, B Drogmoller, G Wright, L van der Merwe, N McGregor, B Chiliza, L Asmal, L Koen, D Niehaus, R Emsley, L Warnich
42. Effects of diet, smoking and alcohol consumption on disability (EDSS) in people diagnosed with multiple sclerosis
S Janse van Rensburg, W Davis, D Geiger, F J Cronje, L Whati, M Kidd, M J Kotze
43. The clinical utility of neuroimaging in an acute adolescnet psychiatric inpatient population
Z Khan, A Lachman, J Harvey
44. Relationships between childhood trauma (CT) and premorbid adjustment (PA) in a highly traumatised sample of patients with first-episode schizophrenia (FES)
S Kilian, J Burns, S Seedat, L Asmal, B Chiliza, S du Plessis, R Olivier, R Emsley
45. Functional and cognitive outcomes using an mTOR inhibitor in an adolescent with TSC
A Lachman, C van der Merwe, P Boyes, P de Vries
46. Perceptions about adolescent body image and eating behaviour
K Laxton, A B R Janse van Rensburg
47. Clinical relevance of FTO rs9939609 as a determinant of cardio-metabolic risk in South African patients with major depressive disorder
H K Luckhoff, M J Kotze
48. Childhood abuse and neglect as predictors of deficits in verbal auditory memory in non-clinical adolescents with low anxiety proneness
L Martin, K Martin, S Seedat
49. The changes of pro-inflammatory cytokines in a prenatally stressed febrile seizure animal model and whether Rhus chirindensis may attenuate these changes
A Mohamed, M V Mabandla, L Qulu
50. Influence of TMPRSS6 A736v and HFE C282y on serum iron parameters and age of onset in patients with multiple sclerosis
K E Moremi, M J Kotze, H K Luckhoff, L R Fisher, M Kidd, R van Toorn, S Janse van Rensburg
51. Polypharmacy in pregnant women with serious mental illness
E Thomas, E du Toit, L Koen, D Niehaus
52. Infant attachment and maternal depression as predictors of neurodevelopmental and behavioural outcomes at follow-up
J Nothling, B Laughton, S Seedat
53. Differences in abuse, neglect and exposure to community violence in adolescents with and without PTSD
J Nothling, S Suliman, L Martin, C Simmons, S Seedat
54. Assessment of oxidative stress markers in children with autistic spectrum disorders in Lagos, Nigeria
Y Oshodi, O Ojewunmi, T A Oshodi, T Ijarogbe, O F Aina, J Okpuzor, O C F E A Lesi
55. Change in diagnosis and management of 'gender identity disorder' in pre-adolescent children
S Pickstone-Taylor
56. Brain network connectivity in women exposed to intimate partner violence
A Roos, J-P Fouche, B Vythilingum, D J Stein
57. Prolonged exposure treatment for PTSD in a Third-World, task-shifting, community-based environment
J Rossouw, E Yadin, I Mbanga, T Jacobs, W Rossouw, D Alexander, S Seedat
58. Contrasting effects of early0life stress on mitochondrial energy-related proteins in striatum and hippocampus of a rat model of attention-deficit/ hyperactivity disorder
V Russell, J Dimatelis, J Womersley, T-L Sterley
59. Attention-deficit hyperactivity disorder in adults: A South African perspective
R Schoeman, M de Klerk, M Kidd
60. Cognitive function in women with HIV infection and early-life stress
G Spies, C Fennema-Notestine, M Cherner, S Seedat
61. Changes in functional connectivity networks in bipolar disorder patients after mindfulness-based cognitic therapy
J A Starke, C F Beckmann, N Horn
62. Post-traumatic stress disorder, overweight and obesity: A systematic review and meta-analysis
S Suliman, L Anthonissen, J Carr, S du Plessis, R Emsley, S M J Hemmings, C Lochner, N McGregor L van den Heuvel, S Seedat
63. The brain and behaviour in a third-trimester equivalent animal model of fetal alcohol spectrum disorders
P C Swart, C B Currin, J J Dimatelis, V A Russell
64. Irritability Assessment Model (IAM) to monitor irritability in child and adolescent psychiatric disorders.
D van der Westhuizen
65. Outcome of parent-adolescent training in chilhood victimisation: Adaptive functioning, psychosocial and physiological variables
D van der Westhuizen
66. The effect of ketamine in the Wistar-Kyoto and Sprague Dawley rat models of depression
P J van Zyl, J J Dimatelis, V A Russell
67. Investigating COMT variants in anxiety sensitivity in South African adolescents
L J Zass, L Martin, S Seedat, S M J Hemming
Assuring Safe Implementation of Decision Support Functionality based on Data-driven Methods for Ship Navigation
No full textThe rapid technology development related to machine learning and data-driven models for autonomous and unmanned vessels continues. Also manned vessels can make use of this technology, for example to enhance situational awareness of an on board navigator. Potentially, this can contribute to increase safety and to optimize operations by transferring tasks and functions to where they are most effectively handled, ashore and on board. However, the introduction of decision support systems and functionality to enhance situational awareness can have detrimental consequences, due to for example misunderstandings, wrong use of the functionality, malfunctioning user-interface, as well as bad or wrong decision proposals. This can be the case, even when manning levels are kept unchanged. To ensure safety, we argue that the system must be rigorously tested, and the system’s limitations, uncertainties and capabilities must be correctly conveyed to its users. Based on current regulations, including the International Maritime Organization (IMO) resolution Principles of minimum safe manning, we investigate how minimum safe manning of a vessel should be established considering relevant factors, including the ship’s level of automation and shore support. We also discuss challenges related to lack of specification, which is an inherent challenge to decision support systems based on object detection and image classification since these tasks rely on perception of the environment, which can only partially be specified using rules. Furthermore, challenges related to lack of explainability are discussed, and potential benefits of using methods for black-box explanation during operation and during testing are investigated. We emphasize the importance of testing and verification of the dataset used to train the models, ensuring that it sufficiently covers relevant scenarios. We also discuss challenges related to human factors, and emphasize the importance of safety management systems used to identify risks, responsibilities, resources and competencies ensuring compliance with rules and regulations.publishedVersio
