Frequently Asked Questions

  • Modelling Group is not just a team, but a collective of seasoned professionals with a minimum of 15-20 years of experience in the industry. Our staff have honed their skills in a wide variety of roles, both in the public and private sectors, and across diverse consultancies from smaller firms to large, international multi-disciplinary organisations.
    Our team members are leaders in their field, having spent many years perfecting and broadening their knowledge. They have extensive experience in building, auditing, and training staff in modelling, managing teams, and working on a vast array of projects in every area of traffic and pedestrian modelling.


    At Modelling Group, we combine this wealth of experience with technical expertise and innovative solutions to tackle complex challenges in transport planning. We use advanced modelling techniques and work closely with clients and regulatory bodies to ensure our models meet the highest standards and contribute to effective urban planning.


    Choosing Modelling Group means choosing a partner with a deep understanding of the industry, a commitment to excellence, and a proven track record of delivering results.

  • Traffic modelling is crucial for understanding and predicting traffic flow, congestion, and transportation infrastructure needs. It helps in planning and designing efficient transportation systems, assessing the impact of new developments, and making informed decisions about traffic management and policy.


    For larger projects, traffic modelling is often a requirement as part of the traffic assessment. It provides a detailed analysis of how the project will impact the existing transportation network, which is essential for obtaining planning permissions and ensuring the project is viable.


    Traffic modelling can also be used to quantify the level of disruption caused by a project. This is particularly important during the construction phase, where traffic patterns may be temporarily altered. By predicting these disruptions, strategies can be developed to minimise their impact.
    Furthermore, traffic modelling plays a key role in negotiations with local authorities. It can help determine the financial contributions that developers need to make towards infrastructure improvements or traffic management measures. These contributions, often referred to as Section 106 agreements in the UK, are designed to offset the impact of the development on the local community.


    In addition, Active Travel England is an official statutory consultee on all planning applications for development equal to or exceeding 150 housing units. The operation of transport networks is incredibly important when dealing with active modes. Microsimulation modelling is the only tool that can model, in detail, all transport modes, making it an invaluable tool in these consultations.


    In summary, traffic modelling is an essential tool in transport planning. It provides valuable insights that inform decision-making, ensure compliance with regulations, and contribute to the creation of sustainable and efficient transportation systems.

  • Traffic modelling is a powerful tool that plays a pivotal role in the planning and design of our transportation systems. It's a method that uses mathematical and computational models to simulate, analyse, and predict traffic flow, congestion, and transportation infrastructure needs.

    Imagine a city bustling with vehicles, pedestrians, cyclists, and public transport. Each element is moving, interacting, and contributing to the overall traffic scenario. Traffic modelling captures this complexity and transforms it into a manageable, understandable model. It's like having a miniature city at your fingertips, where you can observe, experiment, and strategise.

    The beauty of traffic modelling lies in its ability to represent real-world traffic scenarios. It can mimic the morning rush hour, or the gradual increase of vehicles during the evening. It can show us how a new road might alleviate congestion or how a different traffic light sequence could improve flow.

    But traffic modelling goes beyond just simulation. It provides valuable insights that help urban planners, traffic engineers, and policymakers make informed decisions. Whether it's deciding where to place a new bike lane, determining the impact of a new retail centre on traffic, or planning for future population growth, traffic modelling is there to provide data-driven guidance.

    In essence, traffic modelling is not just about understanding today's transportation challenges. It's about shaping the future of our cities and contributing to safer, more efficient, and more sustainable transportation systems.

  • The process typically involves the following steps:
    • Define the scope of the project
    • Collect and analyse traffic data
    • Develop the traffic model using appropriate software
    • Calibrate and validate the model against real-world observations
    • Run simulations to test various scenarios
    • Analyse the results and make recommendations

  • Microsimulation models individual vehicles or pedestrians within a transportation network. It can model complex interactions, vehicle behaviours, and complex traffic control systems. It’s particularly useful for detailed analysis of network interactions in specific locations or scenarios.

  • VISSIM is a microsimulation software that provides detailed modelling of traffic flow, allowing for the simulation of individual vehicles and their interactions. It’s particularly useful for complex scenarios that involve multiple modes of transport, intricate traffic controls, or detailed pedestrian movements. While SATURN and LinSig are powerful tools, they may not offer the same level of detail in certain scenarios.

  • • Strategic or Tactical Macro-Simulation Models: These are high-level models used for long-term planning and policy decisions. They typically cover large areas, such as entire cities or regions, and model traffic at an aggregate level. They are used to assess the impact of major infrastructure changes, policy interventions, or long-term trends like population growth or changes in travel behaviour.
    • Microsimulation Models: These models operate at a more detailed level, simulating the behaviour of individual vehicles or pedestrians within a transportation network. They are often used for more detailed analysis of specific locations or scenarios, such as a particular intersection or corridor, or for assessing the impact of smaller-scale changes like the introduction of a new traffic signal or lane reconfiguration.
    • Deterministic Junction Models: These are often used for optimising individual junctions or intersections. They use deterministic algorithms to predict the behaviour of traffic at a junction based on specific inputs, such as traffic volumes and signal timings. They are typically used for detailed design and optimisation of junction operations.

    In terms of their interactive relationship, each level of model can inform the other. For example, a strategic macro-simulation model might identify a potential issue at a particular location, which could then be analysed in more detail using a microsimulation model. Similarly, the results of a deterministic junction model could be used to inform the design of junctions within a microsimulation model. In this way, the different types of models can work together to provide a comprehensive understanding of traffic behaviour and impacts at multiple scales and levels of detail.

  • Traffic modelling, especially microsimulation, can seem like a significant investment due to its complexity and the level of detail it provides. Microsimulation models simulate individual vehicles or pedestrians, requiring more data and computational resources than traditional deterministic models. Additionally, the software licenses for microsimulation tools can be costly.

    Another key factor is the time and resources it takes for a modeller to become an experienced specialist. The level of pay and training involved to have senior experts on board adds to the cost. These experts are crucial in ensuring the accuracy and effectiveness of the models.

    However, the cost of traffic modelling can vary widely depending on the project’s complexity, the software used, and the level of detail required. While the upfront costs might seem high, we confidently assert that the value it provides will outweigh the initial investment.

    Traffic modelling is crucial for informed decision-making and efficient planning. It helps in understanding and predicting traffic flow, congestion, and transportation infrastructure needs. The increased accuracy and detail provided by microsimulation models, backed by the expertise of seasoned professionals, are not just justified, but essential. They lead to more effective solutions, better planning, and ultimately, significant cost savings in the long run.

  • An independent, external audit provides an unbiased review of the model. It ensures that the model meets industry standards and best practices, and that the results are reliable. An external audit can also identify potential issues or improvements that may be overlooked by the team that developed the model. This process enhances the credibility and reliability of the model.

  • While internal audits can be useful and are certainly an essential part of our quality assurance process, they may not provide the same level of objectivity as an external audit. The team that developed the model may be too close to the project to identify potential issues or biases. An external auditor brings a fresh perspective and can provide a more thorough and unbiased review.