Across the UK, local authorities and city planners urgently require strategies that will reduce the number of vehicles on our roads, decrease congestion, and improve air quality. One of the options being considered is ridesharing; the notion that vehicles should carry more than one passenger to a shared destination. However, this requirement comes with its own set of difficulties, not least an entrenched human preference to own a private vehicle for personal usage. To find a solution requires a greater understanding of where the challenges lie, particularly in terms of the complex inner workings of human decision-making. In a call for further research, TRL is pushing for an increased understanding of how we can shift attitudes to transport options available, and away from the comforts habitually associated with the private vehicle. This will not only help to effectively introduce solutions like ridesharing, it will also help to educate end-users on the need to look further than the personal gains private transport can offer.
Ridesharing – an explanation
Ridesharing is often used as a catch all term to describe journeys which involve more than one passenger. Other terms such as ridehailing, carsharing and ridesourcing are also used to describe similar journeys, though these terms are becoming increasingly differentiated as new avenues of research develop (e.g. ensuring replicability) and as the industry continues to embed research and practice. As such, the SAE taxonomy defines ridesharing as “the formal or informal sharing of rides between drivers and passengers with similar origin-destination pairings” (SAE, 2018, p.8 1). The taxonomy aims to generate a distinction between journeys that are purposefully designed to be shared and those that are more incidental in the amount of passengers being carried.
All of these iterations of the vehicle sharing economy have one key thing in common: they have been introduced and promoted as measures to enable social and environmental changes. While there are important challenges to overcome in these areas (terms such as ‘urbanisation’, ‘ageing population’, as well as increasing concerns over pollution and congestion come to mind), the reality is that the ultimate success of ride and carsharing services will lie in a mass shift away from the private vehicle. Herein may lie one of the key issues to increasing uptake of ridesharing services, as ridesharing has not been designed as a transport solution that directly benefits the end user.
While we may want to believe that we, as individuals, are guided by altruistic principles in our everyday decisions, some evidence may suggest that – when it comes to making subjective appraisals of rewards (and possibly, benefits) – we may favour immediate, personal rewards over long-term incentives for others. Research in this area tends to refer to the concept of temporal discounting (TD); this is, generally speaking, the subjective value placed on rewards as a function of time (Green, Myerson & McFadden, 1997 3); time (particularly, delays to an outcome) being a key mediator of choice behaviour. Research on TD usually involves hypothetical monetary rewards as participants run through a series of questions where they make a choice between, say, £10 now and £50 in a year. Because of this, it has been widely used as a proxy for impulsivity in groups such as adolescents, gamblers and people with neurological disorders and/ or brain injuries.
However, what happens when you apply this concept to pro-social behaviours (e.g. the psychological reward of engaging in altruistic behaviour), or social discounting, to the challenge of promoting ridesharing? Particularly as we consider the premise that to date, ridesharing has not been primarily designed to benefit the end-user.
Research on social discounting has suggested that there are factors that may increase the likelihood of (what is usually, in this line of research, termed as) altruistic behaviour. For example, some research has shown that an immediate personal reward is more likely to be forgone in the presence of an immediate reward for others (e.g. people show a tendency to behave more altruistically when the choice is between an immediate reward for self vs. an immediate reward for another); however, when delays are introduced into the equation – e.g. when the choice is between an immediate, personal reward and a delayed reward for someone else – people are more likely to favour the personal reward (Yi, Charlton, Porter, Carter & Bickel, 2011)4 .
While the research on temporal and social discounting usually relates to hypothetical financial gains, rather than wider social rewards (including concepts such as reduced congestion and pollution), the principles may still apply in areas such as transport choices and innovations. This is supported by uptake theories such as the Diffusion of Innovations theory (DoI, Rogers, 1962 5) as, according to this theory individuals will evaluate (and accept) new ideas and/ or innovations based on appraisals of how these align with their own experiences and needs. For example, among other principles, the DoI suggests that an individual will be more likely to adopt a new idea that is perceived to have a greater relative advantage to what it is replacing. The same theory incorporates the concept of ‘compatibility’, which relates to how compatible the new idea is to the individual’s values and needs.
The question we are left with is, therefore, how compatible are ridesharing services with individuals’ needs? And what are the personal advantages to the individual, particularly when comparing what is viewed as an immediate, personal reward (the convenience and comfort of the private vehicle), versus the longer-term reward for others (positive societal and environmental outcomes)?
Can ridesharing be successful?
This is not to say that ridesharing (and similar services, such as carsharing and ridesourcing) can’t be successful. On the contrary, knowledge of where the challenges lie, particularly when we consider the complex inner workings of human decision-making, will help develop strategies to overcome these. Just to consider a few, a more detailed look at some of the research on social discounting suggests that adding a delay to both the reward to self and others could result in more altruistic behaviour, particularly when the others are known to the individual (e.g. forgoing the personal reward in lieu of a reward for a friend or family member) (Yi et al., 2011)6 . There is also an increasing view that innovations such as vehicle automation and Mobility-as-a-Service (MaaS) may be key enablers of ridesharing services. This is supported (in part, and with its own caveats) by the fact that a large part of the published literature on automated vehicle (AV) public perceptions shows that people’s feelings about AVs range from neutral to positive, with very few usually reporting negative feelings about the technology (see Fernández-Medina, et al. 2018, for results from a real-world trial of an AV shuttle7 ; desk-based research shows similar findings, see König & Neumayr, 2017, for a study including respondents from a number of different countries). Similarly, although currently the private vehicle remains as the ‘gold standard’ of transport convenience, theories such as the DoI suggest that shifting the way people view the transport options available to them could help support increased uptake of such innovations. As such, underpinning the benefits to the individual from ride and carsharing will be paramount. This will not only help by enabling tailored services that can rival and, in some instances, surpass the private vehicle; it will also remove the separation between the individual, the immediate reward (e.g. a convenient, comfortable, affordable journey – or whatever features are most valued by customers) and the ultimate societal benefits that could be realised with increased uptake of ride and carsharing.