Towards using Interval-Valued responses in Service Quality Measurement: A Study in Rail

Lead Research Organisation: University of Nottingham
Department Name: School of Computer Science


Service quality measurement is vital for service providers' development and growth. However, assessing service quality is inherently challenging due to well-established service characteristics such as intangibility, heterogeneity, and inseparability. Extant research has focused on this area and developed various models. The majority used models such as SERVQUAL predominantly utilising surveys to collect customers' subjective feedback.

While substantial research has examined appropriate survey contents and structures, the measurement scales employed in these surveys remain largely unchanged. Specifically, single-point scales, such as the 5- or 7-point Likert scales, are predominantly utilised. These scales, which restrict participants to selecting single predefined values, limit customers' authentic expression.

From a computer science perspective, a possible solution is the employment of Interval-Valued Scales (IVSs). IVSs enable respondents to select an interval by positioning an ellipse on a straight line with polar adjectives at each end. Consequently, interval-valued responses offer richer, more detailed information compared to single-point scales. They provide researchers with greater insight into respondent perceptions and uncertainty. Moreover, as IVSs do not have prefixed choices, respondents have complete freedom in expressing their evaluations, capturing individual differences [3] [4] [5].

This PhD research investigates the potential of IVSs for measuring the UK rail industry's service quality. Rail transportation, regarded as one of the safest, most effective, and most environmentally friendly ways to travel, is an important mode of transport in Great Britain. Thus, comprehending rail service quality from the customer's viewpoint is critical. To achieve this, the government, in collaboration with organisations like Transport Focus, conducts weekly and yearly surveys with passengers. This PhD research aims to improve the current survey methods, capturing richer information from UK rail customers by using IVSs, and thereby delivering an enhanced understanding of rail service quality. It has the potential to assist the rail industry in better identifying customer needs and developing accordingly.

Planned Impact

We will collaborate with over 40 partners drawn from across FMCG and Food; Creative Industries; Health and Wellbeing; Smart Mobility; Finance; Enabling technologies; and Policy, Law and Society. These will benefit from engagement with our CDT through the following established mechanisms:

- Training multi-disciplinary leaders. Our partners will benefit from being able to recruit highly skilled individuals who are able to work across technologies, methods and sectors and in multi-disciplinary teams. We will deliver at least 65 skilled PhD graduates into the Digital Economy.

- Internships. Each Horizon student undertakes at least one industry internship or exchange at an external partner. These internships have a benefit to the student in developing their appreciation of the relevance of their PhD to the external societal and industrial context, and have a benefit to the external partner through engagement with our students and their multidisciplinary skill sets combined with an ability to help innovate new ideas and approaches with minimal long-term risk. Internships are a compulsory part of our programme, taking place in the summer of the first year. We will deliver at least 65 internships with partners.

- Industry-led challenge projects. Each student participates in an industry-led group project in their second year. Our partners benefit from being able to commission focused research projects to help them answer a challenge that they could not normally fund from their core resources. We will deliver at least 15 such projects (3 a year) throughout the lifetime of the CDT.

- Industry-relevant PhD projects. Each student delivers a PhD thesis project in collaboration with at least one external partner who benefits from being able to engage in longer-term and deeper research that they would not normally be able to undertake, especially for those who do not have their own dedicated R&D labs. We will deliver at least 65 such PhDs over the lifetime of this CDT renewal.

- Public engagement. All students receive training in public engagement and learn to communicate their findings through press releases, media coverage.

This proposal introduces two new impact channels in order to further the impact of our students' work and help widen our network of partners.

- The Horizon Impact Fund. Final year students can apply for support to undertake short impact projects. This benefits industry partners, public and third sector partners, academic partners and the wider public benefit from targeted activities that deepen the impact of individual students' PhD work. This will support activities such as developing plans for spin-outs and commercialization; establishing an IP position; preparing and documenting open-source software or datasets; and developing tourable public experiences.

- ORBIT as an impact partner for RRI. Students will embed findings and methods for Responsible Research Innovation into the national training programme that is delivered by ORBIT, the Observatory for Responsible Research and Innovation in ICT ( Through our direct partnership with ORBIT all Horizon CDT students will be encouraged to write up their experience of RRI as contributions to ORBIT so as to ensure that their PhD research will not only gain visibility but also inform future RRI training and education. PhD projects that are predominantly in the area of RRI are expected to contribute to new training modules, online tools or other ORBIT services.


10 25 50

Studentship Projects

Project Reference Relationship Related To Start End Student Name
EP/S023305/1 30/09/2019 30/03/2028
2617017 Studentship EP/S023305/1 30/09/2021 29/09/2025 Yu Zhao