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，由于已建立的服务特征（如无形性、异质性和不可分割性），评估服务质量本质上是具有挑战性的。现有的研究主要集中在这一领域，并开发了各种模型。大多数使用SERVQUAL等模型，主要利用调查来收集客户的主观反馈。虽然有大量的研究审查了适当的调查内容和结构，但这些调查所采用的测量尺度基本保持不变。具体来说，主要使用单点量表，如5点或7点李克特量表。这些量表限制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使用区间值量表（IVSs）。ivs通过在直线上定位一个椭圆，两端有极性形容词，使被调查者能够选择一个间隔。因此，与单点量表相比，区间值回答提供了更丰富、更详细的信息。他们为研究人员提供了更深入的了解受访者的看法和不确定性。此外，由于ivs没有前缀选择，受访者可以完全自由地表达自己的评价，捕捉个体差异[3]b[4][5]。这项博士研究调查了IVSs在衡量英国铁路行业服务质量方面的潜力。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。为此，政府与Transport Focus等组织合作，对乘客进行每周和每年的调查。这项博士研究旨在改进当前的调查方法，通过使用IVSs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识别客户需求并据此发展。

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.