Complexity, Requirements and Design

So why do we get worried about complex systems and what can we do about it? Complexity worries us because the world is unpredictable, large scale, multi component and densely interconnected. We perceived interactions as complex since we have difficulty in generalising over multiple events especially when events are poorly ordered. However interactional complexity is tractable by mathematical modeling as (misnamed) chaos theory has shown. Interactional complexity is being modeled with increasing accuracy by computational theories and simulations of physical and biological systems, viz. the IPCC world climate model. The second form is semantic complexity which implicates the difficulties we have in understanding intent of people. Here sadly there is no short term tractable solution. The Dagstuhl process of discussion leading to incremental (maybe radical) advances in understanding is one answer

Requirements Engineering Domain Dimensions

This doc gives my initial ideas on the dimensions/criteria for different genres of applications (or domains if you prefer), following my summary presentation at the Dagstuhl workshop

Evaluating User Engagement Theory

A variety of views of User Experience (UX) have emerged ranging from contextual interpretations of experience to experimental studies. This paper focuses on User Engagement (UE), a restricted explanation of UX that concentrates on judgement of product quality during interaction. It presents a model to explain how users’ judge quality according to criteria such as aesthetics, usability and engagement

Known and unknown requirements in healthcare

We report experience in requirements elicitation of domain knowledge from experts in clinical and cognitive neurosciences. The elicitation target was a causal model for early signs of dementia indicated by changes in user behaviour and errors apparent in logs of computer activity. A Delphi-style process consisting of workshops with experts followed by a questionnaire was adopted. The paper describes how the elicitation process had to be adapted to deal with problems encountered in terminology and limited consensus among the experts. In spite of the difficulties encountered, a partial causal model of user behavioural pathologies and errors was elicited. This informed requirements for configuring data- and text-mining tools to search for the specific data patterns. Lessons learned for elicitation from experts are presented, and the implications for requirements are discussed as “unknown unknowns”, as well as configuration requirements for directing data-/text-mining tools towards refining awareness requirements in healthcare applications

Which computer-use behaviours are most indicative of cognitive decline? Insights from an expert reference group

Computer use is becoming ubiquitous amongst older adults. As computer-use depends on complex cognitive functions, measuring individuals’ computer-use behaviours over time may provide a way to detect changes in their cognitive functioning. However, it is uncertain which computer-use behaviour changes are most likely to be associated with declines of particular cognitive functions. To address this, we convened six experts from clinical and cognitive neurosciences to take part in two workshops and a follow-up survey to gain consensus on which computer-use behaviours would likely be the strongest indicators of cognitive decline. This resulted in a list of twenty-one computer-use behaviours that the majority of experts agreed would offer a ‘strong indication’ of decline in a specific cognitive function, across Memory, Executive function, Language, and Perception and Action domains. This list enables a hypothesis-driven approach to analysing computer-use behaviours predicted to be markers of cognitive decline

The development and validation of a scoring tool to predict the operative duration of elective laparoscopic cholecystectomy

Background: The ability to accurately predict operative duration has the potential to optimise theatre efficiency and utilisation, thus reducing costs and increasing staff and patient satisfaction. With laparoscopic cholecystectomy being one of the most commonly performed procedures worldwide, a tool to predict operative duration could be extremely beneficial to healthcare organisations. Methods: Data collected from the CholeS study on patients undergoing cholecystectomy in UK and Irish hospitals between 04/2014 and 05/2014 were used to study operative duration. A multivariable binary logistic regression model was produced in order to identify significant independent predictors of long (> 90 min) operations. The resulting model was converted to a risk score, which was subsequently validated on second cohort of patients using ROC curves. Results: After exclusions, data were available for 7227 patients in the derivation (CholeS) cohort. The median operative duration was 60 min (interquartile range 45–85), with 17.7% of operations lasting longer than 90 min. Ten factors were found to be significant independent predictors of operative durations > 90 min, including ASA, age, previous surgical admissions, BMI, gallbladder wall thickness and CBD diameter. A risk score was then produced from these factors, and applied to a cohort of 2405 patients from a tertiary centre for external validation. This returned an area under the ROC curve of 0.708 (SE = 0.013, p  90 min increasing more than eightfold from 5.1 to 41.8% in the extremes of the score. Conclusion: The scoring tool produced in this study was found to be significantly predictive of long operative durations on validation in an external cohort. As such, the tool may have the potential to enable organisations to better organise theatre lists and deliver greater efficiencies in care

Requirements Analysis for Socio-technical System Design

Few methods address analysis of socio-technical system requirements. This paper describes a method for analysing dependencies between users/stakeholders agents and computer systems in the operational environment. Domain scenarios describing the system and its context are used to create an environment model. A method is proposed to define business organisational relationships by operationalising transaction cost theory to obtain an a priori view of relationships according to the market context for a client and supplier. Inter-agent dependencies are investigated to determine the coupling between agents according to type of event flows and dialogue exchanges between them. Coupling metrics are applied to assess the degree of dependencies between the system and the users. High-level requirements are suggested to deal with different types of organisational design. The method is illustrated with two case studies of a service engineer support system and an Internet travel agent

Love it or hate it!: interactivity and user types

This paper investigates general and individual evaluations of User Experience (UX) with interactive web sites. A series of studies investigate user judgment on web sites with different interactivity levels over repeated exposures. The more interactive websites produced more positive affect, had better design quality ratings, which improved with exposure, and were preferred. Differences between the more interactive sites indicated overall UX was influenced by users' preferences for interactive styles, with both sites having enthusiast, potential adopter, and non-adopter users. The implications for models and frameworks of UX are discussed