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

服务质量测量对服务提供商的发展和成长至关重要。然而，评估服务质量本质上是具有挑战性的，由于完善的服务特性，如无形性，异构性和不可分割性。现有的研究集中在这一领域，并开发了各种模型。虽然大量研究已探讨适当的调查内容及结构，但这些调查所采用的量度尺度大致上维持不变。具体而言，主要使用单点量表，如5点或7点李克特量表。这些尺度限制了参与者选择单一的预定义值，限制了客户的真实表达。从计算机科学的角度来看，一个可能的解决方案是采用区间值尺度（IVS）。IVS使受访者能够通过将椭圆定位在两端带有极性形容词的直线上来选择间隔。因此，与单点量表相比，区间值响应提供了更丰富，更详细的信息。它们为研究人员提供了对受访者的看法和不确定性的更深入的了解。此外，由于IVS没有前缀选项，受访者可以完全自由地表达他们的评价，捕捉个体差异[3] [4] [5]。本博士研究调查了IVS测量英国铁路行业服务质量的潜力。铁路运输被认为是最安全，最有效，最环保的旅行方式之一，是英国重要的交通方式。因此，从客户的角度理解铁路服务质量是至关重要的。为了实现这一目标，政府与交通焦点等组织合作，每周和每年对乘客进行调查。这项博士研究旨在改进目前的调查方法，通过使用IVS从英国铁路客户那里获取更丰富的信息，从而提高对铁路服务质量的理解。它有可能帮助铁路行业更好地确定客户需求并进行相应的开发。

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.