J.vandenhoogen@tudelft.nl, Smeijer@kth.se
Abstract. Innovation at a railway network operator depends on the decision-making
processes in the daily work of operational professionals and staff. This paper is about innovative measures at a railway network operator, required to increase capacity on the railway network without investing in expensive infrastructural extensions. Using field observations and open interviews, the authors found out that project managers early on in the decision-making process limit their design space. The range of alternatives under study is limited to decrease the technical and social complexity. By doing so, project managers are able to realize a phased and sequential decision making process that leads to a working proof-of-concept. The solutions are only valid under highly restrictive assumptions. The uncertainty about the value of a solution once implemented in the total railway system therefore remains high and many innovation processes therefore end with the proof-of-concept. This studies’ contribution to existing theory is the provision of an alternate explanation for the rigidity of railway systems and network-based infrastructures in general. Rather than incremental innovations as a result of political decision making in a network of interdependent actors with conflicting incentives, incremental innovations can also be a result of a more sequential and phased decision making processes as project managers purposefully decrease the technical and social complexity beforehand.
Keywords. Decision Making, Process Innovation, Railway Systems,
1 Introduction
Extension of railway capacity in a densely built environment is very expensive, but also much needed given the growing demand for transport. This is very much true in the Dutch situation as in the forthcoming years, the Dutch railway network will have to increase its capacity by 5% annually to accommodate the expected growth in passenger and freight transport (MinIE, 2007). To ensure a total capacity increase of 50% by 2020, the Dutch government has made available a budget of 4.5 billion euros to the parties involved. Notwithstanding certain infrastructural extensions, the main focus of the capacity expansion is a better and more efficient use of existing infrastructure by means of process improvements (ProRail, 2010).
Research on decision-making within the infrastructure sector, and especially the railway sector, has mainly focused on optimization issues in the operational and tactical layers of the organization (see Ingolotti et al., 2004; Podofillini et al., 2006;
Caprara et al., 2007), on large infrastructure projects (see Koppenjan, 2005; Priemus & Leijten, 2005; Priemus et al., 2008; De Bruijn & Veeneman, 2009) or on a combination of these two (see for instance Hooghiemstra et al., 1999 for an overview). For studies on decision-making on so-called mega-projects, most often a network approach is taken and scholars are mainly stemming from the public administration streams of research (see for instance De Bruijn et al., 1996). The authors found that empirical research in decision-making on small-scale process innovations is scarce. An example of such a process innovation is to change the handling schemes of train dispatchers in case of disruptions, or improving the way passengers board the train. The partial focus of these projects on human roles does not perfectly allow for mathematical optimization techniques and these projects are expected to be less prone to political behavior than highly contested mega-projects. This paper contributes an empirical study of how decision making processes apply to these smaller scale process innovations and what factors because these decision making processes to be.
2 Problem situation
ProRail is the railway infrastructure management company of the Netherlands and responsible for the maintenance and operation of the Dutch railway network. Its core business is to provide safe access to railway tracks for train operating companies, either in cargo and passenger transport. The ministry of infrastructure and environment gives ProRail the license to operate per decree on a ten-year basis. Before 1995, ProRail was part of the Dutch Railways (NS) but new European guidelines pushed for a split-up of infrastructure management and the commercial exploitation of passenger services. Ever since, NS has the license to run passenger trains on the so-called ‘core lines’ of the Dutch network – several private companies run trains on regional routes – and ProRail maintains the network, informs travellers and controls traffic.
As operator of the railway network, ProRail is the main responsible party to increase capacity by 50%. ProRail relies heavily on the cooperation of private and semi-private train-operating companies (TOC) that exploit the network commercially and offer services to the passengers. To increase the capacity, the innovative efforts are mostly focused on processes rather than on building new connections or the doubling of tracks. We define process innovations as “new elements introduced into an organization’s production or service operations—input materials, task specifications, work and information flow mechanisms, and equipment used to produce a product or render a service” (Reichstein and Salter, 2006: p.653).
Three reasons for the focus on process innovations show the uniqueness of the situation. First of all, the budget is limited. The ‘Hanze-lijn’ a railway line of 50 kilometers completing the line between Amsterdam and Zwolle will shorten the travel time between the economic heart of the Netherlands and the northern regions by only 15 minutes. However projected costs are around 1 billion euros. 4.5 billion euros therefore cannot be sufficient to resolve nationwide capacity issues by only expanding the network. Second, the sheer lack of freely usable land for railway extensions in a highly populated country like the Netherlands implies that little room exists for laying
new railway tracks. Finally, the expected decline in population will start around 2040 (CBS, 2009) and too much focus on infrastructural extensions will increase the chance of overcapacity once transport demand starts to fall. Taken this into account, the involved parties have opted for a process approach. ProRail, together with Dutch Railways and representative bodies of freight train operators, has created a plan in which a set of measures is deemed sufficient for reaching the capacity increase of 50% by 2020. The main focus lies on doing things differently with the same infrastructure. Highlight of this plan is the aspiration to start a metro-like railway system where on the most important corridors each hour 12 trains depart per direction.
Without the ability to heavily invest in new railway tracks, a set of coherent smaller-scale process innovations are needed to support such an ambition. For instance, passengers need to board trains more quickly and new concepts for traffic control need to be adopted. Our goal is to study these decision-making processes to find out what factors drive the course of actions.
3 Methodology
As our main goal is to give a description of current practices at ProRail, we choose the case study method as most suitable for answering our questions (Yin, 2009). We conduct an in-depth study on the phenomena we are interested in.
This study is part of a larger research project on gaming simulations and decision-making that provides us access to interviewees, possibilities to be present at project meetings and make site visits. Respondents were mainly sought in the innovation department of ProRail, although some of them also worked for other departments. The selection criterion was that they had been involved in small-scale improvement projects in the last two years and as such could tell in detail how they executed these projects. The commissioning of an old railway line between Nijmegen and Kleve is included to allow for a comparison with a more infrastructure focussed project. The authors conducted eight open interviews during which the respondent was asked to describe several projects undertaken. Interviews took about one hour and were taped using a recorder. The interviewers did not give a detailed description of the interview and its goals beforehand. The interview only started with the question what projects had been undertaken in the last two years and if the respondent could describe them. This ensured an open and free interview in which respondents adressed topics as they saw fit.
The authors made field observations between March and August 2011 during railway simulation sessions, project meetings, as well as site visits. We have visited two regional traffic control centers in The Hague and Rotterdam as well as the national traffic control center (OCCR) in Utrecht. A triangulation of data ensured the validity of the final model about decision-making at ProRail. Only interviews could lead to a bias as respondents might rationalize their decisions post-hoc (Child et al., 2009). We were able to look if hypotheses from the interviews could be corroborated by the field observations we made ourselves.
We used a grounded theory approach in which we first gathered data and based on this data build a theory, using the method as proposed by Strauss & Corbin (1990) in which theorizing is only done after data collection. The first author was completely new to the domain of railways and therefore could fulfill the unbiased observation requirement.
4 Findings
The interviews and observations provided a range of projects to study. Seven projects were discussed to such an extent they allowed for analysis. Of these seven, six involved a process innovation and one involved an infrastructure focused project. By doing so, we are able to compare the decision making process on small-scale process innovations with the decision making process on larger-scale infrastructure extensions. Table 1 presents the overview of the interview data in condensed format.
Table 1: Process innovations and their characteristics
1
NAU 2 ETMET 3 GPS tracker 4 Rail-wheel lubricant 5 Count-down 6 Spreading passengers 7 Nijmegen-Kleve Problem Disruptions on Utrecht, central node of the railway network spread out through the network Feasibility of frequency increases on 4 corridors unknown Exact location of trains unknown on certain branches, affected accurate travel information Stricter regulation on noise-pollution, due to rail-wheel friction too much noise emission High variance in dwelling times on stations ETMET showed criticality of dwelling times and waiting passengers as an influential factor Increase in traffic demand between Nijmegen and Kleve
Goal Make Utrecht more robust Test feasibility of an increase in frequency to 14 trains per hour per direction Provide traffic controllers and travel informers with location of trains Decrease rail-wheel friction related noise pollution, later on also to reduce wear and tear and passenger comfort. (to convince NS) Decrease variance in length of departure procedure of trains Decrease dwelling times by allowing for a quicker boarding procedure of passengers Re-install old railway line Contested goals during decision making process? Partly, for NS it was also about lowering work pressure of train controllers n/a No NS is not responsible for noise reduction, therefore other goals were introduced: reducing wear and tear + increasing passenger comfort No No Yes, ranging from building a tram network to making airport Weeze more accessible
Client Board ETMET task force
n/a Asset management department n/a Prorail Traffic Control Euregio Rijn-Waal Involved
parties Many Many Few Few Few Few Many
Restrictio
ns No changes in IT- and safety systems Test on only one corridor out of the 4 corridors No changes in IT- and safety systems. No disruptions for train operations. Lubricant should not have an effect on braking distance No changes in safety systems No permanent changes to railway station Subsidy of EU was directed towards light rail Inhibiting
factors Small measures always involve multiple parties Parallel overlapping developments in departments Departments with different lead times Hard to steer operational personnel of both ProRail and NS Behavior of operational personnel unpredictabl e GPS should be failsafe
Main benefit was for ProRail, but cooperation of NS was needed. Cooperation not guaranteed since benefits for NS were unclear. Test was carried out with smaller TOC, offering more opportunities for experimenting Hard to steer operation al personnel belonging to NS No interference with daily operations of NS Different goals of different parties. Kleve wanted heavy-rail, Groesbeek wanted bus and Nijmegen wanted light-rail
Solution Decrease amount of train interferences, a solution already considered by NS Place GPS on board of trains Use of already existing onboard lubricant to also use for rails
Connect a count-down machine to safety system that tells machinist when to start the departure procedure Provide passengers information about length of train so that they spread more evenly across the platform Unknown Result Implemen-tation of corridor traffic control concept, restricting the use of switches Proof-of-concept / still ongoing Proof-of-concept / still ongoing Proof-of-concept /
still ongoing Proof-of-concept / still ongoing
Proof-of-concept No outcome yet
Remainin g uncertain-ties In what situations do traffic controllers need extra flexibility? Is ETMET feasible in the daily operations without special attention and resources Implemen-tation of POC is time-consuming due to lead times + safety issues Uncertain if operational personnel will use GPS
Effects for lines where multiple trains run are unknown. Effects of trains equipped with lubricant on different segments of railway network are unknown Current machine is not dynamic, not able to communi cate with safety system Value of proof-of-concept unknown when NS cannot predict length of train Value of light-rail dependent on investments of Nijmegen in own light-rail network General remarks about the organizati on Incident-driven culture Short-term focus Compartmen-talization Hierarchical organization Top-down decision making Focus on own departments
Often benefits for Prorail cannot be realized without cooperation of TOCs Risk-averse culture Compartmentaliza tion To ensure coordination, a lot of procedures Focus on solutions, rather than on problems
In a larger versions of Table 1, the authors looked for patterns that explain the decision-making and success of process innovations in railways at the project level. For every pattern found, the full transcripts of the interviews were recalled and checked for correct interpretation of the pattern. The following sub-sections present three hypotheses formulated on 3 patterns found that remained when checked the transcripts.
4.1 Hypothesis 1: Projects are mainly focused on delivering a proof-of-concept
As shown in Table 1, nearly all projects ended up with proof-of-concept. Only NAU project ended up in an implementation, and this implementation is officially a field trial and still under review.
For instance, spreading passengers along the platform was done at a small railway station to see if the measure worked at all. One respondent mentioned that usually new measures are tested in rural parts of the country and if results are positive, tests are done in busier parts of the railway network. We have seen concrete evidence of this at the project on reducing railway friction and the noise pollution this causes. The chosen alternative was one where a lubricant machine would be placed under the trains that directly lubricated the railway tracks as the train traversed the network. This measure was first tested on a regional line with a smaller train operating company before ProRail went to the larger Dutch Railways with the solution.
Through the use of a proof-of-concept, either tested in a simulated environment (projects 1 and 2) or in real-life (projects 1 to 6) projects managers determined the effects a possible solution has and to what extent it helps in solving the central problem. The first reason for a focus on proof-of-concepts is that project managers
needed to be convinced themselves that their solution would be feasible and effective. Without a proof-of-concept, project managers were unsure of how in particular the human elements of the railway system (passengers, operational personnel) would react to the measures. In project 7, the commissioning of a railway line, these substantive considerations were far less prominent. Here, the decision making process was far more about multiple parties achieving their own objectives. Besides that, mere practical arguments can be given for not focusing on a proof-of-concept in real-life for a complete railway line.
Besides proof-of-concepts as a means to convince oneself of the effectiveness of a measure, they also served to convince other parties not yet involved in the decision making process. A partial goal to test the onboard lubricant on the lines operated by Connexxion was to convince NS that this measure was effective in reducing noise pollution. ETMET was a project specifically targeted to achieve a proof-of-concept. The main question during the project was: are we able to increase the frequency on the corridor Amsterdam-Eindhoven given the current infrastructure?
In many cases the proof-of-concepts showed the feasibility of the alternative. The onboard placement of a lubricating machine on the decentralized line between Amersfoort and Ede-Wageningen proved to be effective in reducing noise pollution and informing waiting passengers about the length of a train proved to be effective in spreading them across the platform to ensure a quicker boarding procedure. In other cases, the proof-of-concept showed that the solution would still be infeasible. For instance, the live-test of increasing the frequency to 12 passenger trains per hour on the corridor Amsterdam-Eindhoven showed that the current system is not able to cope with moderate disruptions on such densely utilized parts of the network.
4.2 Hypothesis 2: Concessions are made to arrive at a proof-of-concept quickly
Since project managers cannot predict the effectiveness of a measure, a proof-of-concept proved to be valuable. To quickly come to such a proof-of-proof-of-concept, we saw how project managers early on in the decision making process placed large restriction on the alternatives they would consider. If we define the range of considered
alternatives as the ‘design space’, project managers reduced technical complexity and social complexity by minimizing this design space.
For instance, to decrease the technical complexity, solutions that involved interfering in safety systems and IT-systems were purposefully neglected in projects 1, 3 and 5. Respondents explicitly mentioned that better solutions were most probably forgone but that limiting the design space leads to faster results in a proof-of-concept. Project 1 purposefully followed the measures NS already took to make the Utrecht more robust. In case of project 2, it was chosen to only focus on one corridor (A2) rather than the total four or five that are planned to have this frequency increase. In case of project 6, the solution was designed to work on a railway station with only two platforms, where only one specific regional service stops and under the premise that NS was able to tell in advance the length of the trains. In that way, additional technical complexity of last minute platform changes, different services and unpredictable train lengths was avoided.
Besides a reduction in technical complexity we have seen how project managers also reduced social complexity by not involving too many departments early on in the process. Many respondents mentioned that the organization can be characterized by a plethora of self-reliant islands of many different disciplines. This
compartmentalization is perceived as effective for governing a railway system as long as procedures would ensure a close coordination of activities. However, for
innovation projects this compartmentalization proved to be an inhibiting factor. Many respondents mentioned the need for approval of different departments as a burden. Overlapping change initiatives sometimes ran in parallel to each other. We have observed ourselves how comparable simulators were developed in different departments at the same time without the departments being aware of each other’s activities. In the decision making process, respondents pointed specifically to the different lead times each department had and to the extra demands a department would have if a measure would also involve them. By decreasing this social complexity, project managers were able to more ensure a timely proof-of-concept. This reduction in social and technical complexity by minimizing the design space has led to a manageable decision-making process towards a proof-of-concept. In almost all cases we have seen how the problem formulation and goals were uncontested. In projects 1 and 4 goals were contested but only after the first proof-of-concept was made in a simulated and real-life environment respectively. Furthermore, distinct phases in the decision making process could be distinguished and these phases followed each other sequentially rather than iteratively. In project 7, the participation of multiple parties early on in the decision making process has led to the opposite observation. Problem formulations and goals were highly contested and changed frequently during the decision making process. Where the first goal was to install a light rail link, one municipality reformulated the goal. According to them, the goal was not to build a light rail link but rather to provide a public transport link for which a bus connection would also suffice and would diminish rail-related noise problems for the municipality.
4.3 Hypothesis 3: Concessions lead to uncertainties about the effectiveness of a proof-of concept
What all these proof-of-concepts had in common is that they showed the feasibility or infeasibility of the solution in a closely defined part of the railway system. The restrictions project managers placed on their design space abled them to develop a proof-of-concept but these restrictions inhibited to a large extent the external validity of their findings. In all cases where a proof-of-concept was made, projects managers were uncertain about the effectiveness of their measure if it would implemented in the total railway network.
For instance, showing information about the length of a train proved to be effective but only under the assumption that NS could guarantee a predictable schedule about the length of the trains. Furthermore the solution was tested on a station with only one platform per direction, leaving out the possibility for last minute changes in departure platforms. It therefore remained highly uncertain to what extent the solution would be effective on a railway station with twelve platforms, serviced by different train
operating companies and with a dynamic length of trains. The lubricating machine was effective but only on a part of the network where just one type of train ran and its effectiveness on parts where multiple types of trains with different speeds is still questioned by the involved project managers.
The many uncertainties about the effectiveness of these proof-of-concepts once implemented in the complete railway system caused almost all projects to end up without a clear implementable result. Project 1 is one the exceptions to this finding as the project resulted in an implementation of the alternative that increased the robustness of the central node of the Dutch network to minor disruptions. The proof-of-concept during this project was tested in a simulated environment that through the use of gaming elements made less restrictive assumptions than the other projects for which the proof-of-concept was tested in real-life.
4.4 Discussion
Our results show that decision makers consider the railway systems as technically complex and that the configuration of decision makers responsible for different parts of this system, adds to the social complexity. Furthermore we have shown that of all the process innovations projects only a handful were implemented and that this leads to incremental steps being taken rather than radical or breakthrough innovations. Existing research on railway systems and network-based infrastructures in general acknowledges that infrastructures are characterized by technical and social complexity (Herder et al., 2008) leaving little opportunity for one actor to solve the problem on its own (De Bruijn and Herder, 2009). The complexity of railway systems therefore favors incremental innovations (Geyer and Davies, 2000; Bontekoning and Priemus, 2004; Geels, 2005).
The causal story explaining how complexity leads to incremental innovations differs from what we have seen at ProRail. Our study therefore provides an alternate causal path from complexity towards incrementalism. In literature, the interdependence between elements of the technical system and the social system leads to many actors with different incentives being involved in the decision making process. Incumbents have vested interests in the status quo and due to sunk costs and lock-in effects, the compromises that inherently follow from such political decision making processes lead to incremental steps being taken rather than radical breakthroughs (Geels, 2005). Railway systems therefore follow technological trajectories (Dosi, 1982): problems are solved on the ground of a technological paradigm.
However, we have seen how by limiting the technical and social complexity beforehand, project managers were able to decrease the amount of political behavior in decision making. Rather than a network of actors with different goals, incentives and opinions about valuable information and the decision itself (De Bruijn & Herder, 2009) we see that a phased decision making approach can be distinguished in the process towards a proof-of-concept. By purposefully limiting the ‘politicalness’ inherently associated with technically and socially complex issues, project managers were able to quickly deliver a proof-of-concept. The restrictive assumptions under which a proof-of-concept is valuable cause the uncertainties about the feasibility of the proof-of-concept once implemented in the complete railway system to remain
high, to the project managers themselves, as well as to the other parties. Only one of the studied projects therefore achieved implementation.
5 Conclusion
Our study shows that the decision making process on small-scale process innovations is phased and sequential. Unlike for mega-projects, political behavior due to misaligned incentives, differing goals and contested problem formulations and information seems to be lacking. By purposefully limiting the design space and restricting the amount of viable alternatives, project managers were able to quickly deliver a proof-of-concept. With a limited design space, project managers were able to decrease the social and technical complexity that characterizes network-based infrastructures and railway systems more specifically. In most cases, the resulting proof-of-concept proved to be feasible but only under very restrictive assumptions. In almost all cases, the uncertainty about how the railway system would behave if the solution would be implemented in real-life caused many proof-of-concepts to remain just that: a proof that the concept could work, in theory.
This study therefore adds an alternate explanation for the rigidity of railway systems. Rather than being a result of a political decision making process between different actors with differing interests, incremental innovation can also stem from a phased decision making process. Current theory, according the researchers, overlooks the fact that project managers responsible for process innovations are able to early on in the decision making process decrease the technical and social complexity by limiting the design space. Only those alternatives were considered that could be easily developed into a proof-of-concept and according to all respondents, the more departments were involved, the more time it would take. Due to this, goals and problem formulations remained stable and uncontested and the process resembled a phased and sequential process.
It remains a question whether the observed patterns are the best solution possible in the given situation, or that the remaining uncertainty can be managed better. Future research will investigate the role of different tools and techniques like case studies, expert meetings, computer simulation and gaming simulation on the reduction of uncertainty and decrease in design space in process innovation.
Acknowledgements. The authors thank the interviewees and contacts at ProRail for
their cooperation, and ProRail for funding this research.
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