How can you successfully estimate time and costs?

  5 February 2024
  Method    , ,

The challenge of each estimate is to identify the most realistic value possible, so that at the end of the project, the difference between the estimated value and the actual value is as small as possible.

To get as close as possible to this realistic value, I use the following approach:

  1. I start by noting the value that comes to me intuitively, whatever it may be.
  2. I use one or more of the following estimation methods:
    • By breakdown. Breaking down the element to be estimated into sub-elements, up to a level at which it becomes possible to make an estimate.
    • Expert judgement. Consultation with people experienced in the field related to the item being valued.
    • Estimation by analogy. Reference to similar projects or project elements whose value is known through experimentation, while adapting this value to the new context.
    • Parametric estimation. Estimate based on statistical data specific to the field of the element being estimated.
    • Mean value. Calculation of an average value, based on the most optimistic value and the most pessimistic value.
    • Poker planning. Collaborative and consensual estimation method, using a pack of cards bearing different values.
  3. I add to the value obtained a reserve linked to the level of uncertainty in the estimate. This reserve can range from 10% to cover a minor contingency to 300% for highly uncertain situations. For very specific projects, some people use the pi-figure method to define the reserve to be included in their estimates.
  4. I compare the intuitive value with the value established using one of the above methods. If they are consistent, I have sufficient confidence in the value established. If the values are inconsistent, I redo the intuitive estimate and use other methods.

The pi-figure method

The pi-figure method is entirely empirical and can be interpreted by the fact that a non-performing team spends 3x as much time carrying out the tasks it has estimated and that there is 3x as much work behind the unknown tasks.

The method therefore consists of combining these two factors to estimate the amount by which the value should be multiplied to include the reserve, according to the following rules:

  • π^2 when the project team is not yet performing well and is doing something it does not know how to do,
  • π when the project team is not yet performing well but is doing something it knows how to do,
  • π when the project team is performing well but doing something they don’t know anything about,
  • √π when the project team is performing well and doing something it knows how to do.

5 steps to choosing the right deadline management tool

  9 January 2024

One of the keys to successful projects is controlling deadlines. This requires good planning and coordination of the work needed to deliver the final results expected at the end of the project.

Here are the 5 steps I use to keep my project deadlines under control.

  1. Determining the complexity of the project. An uncomplicated project is one where the strategic stakes are relatively low, the entire project lasts from a few weeks to a few months, the team consists of a few known people, the environment is known and the budget is a few thousand francs at most. A complex project is one in which one or more of its parameters is strong or high.
  2. Determine the predictability of the project. A predictable project is one where you can easily determine the course, activities, costs, stakeholders and risks before the project starts. A poorly predictable project is one in which one or more of its parameters is difficult to estimate in advance.
  3. Understanding the project environment. The choice of project management method and planning tools depends on the organisation’s environment. It depends, for example, on the tools already in use, established procedures, IT security rules or licence costs. The choice also depends on the habits and skills of the team.
  4. Choosing the management method. Depending on the predictability and the environment, you can determine whether the most appropriate method is an agile method (e.g. SCRUM), a predictive method (e.g. Hermes, IPMA, PMBOK) or a versatile approach such as Circular Project Management, which allows both approaches.
  5. Choosing the scheduling tool. For less complex projects, I make do with a list of tasks and a summary schedule, or even a few key milestones. For projects that follow an agile approach, I use a phase plan and Kanban boards. Finally, for complex projects that follow a predictive approach, I use a specialised planning tool (e.g. Merlin Project, Microsoft Project). There are a wide variety of IT tools available for planning projects: tools offering Kanban (e.g. Trello, WeKan, OpenProject), tools specialising in Gantt charts (e.g. GanttProject, ProjectLibre, Microsoft Project) or multi-functional tools (e.g. Jira, Asana). At Prefix, I use Merlin Project, a very comprehensive tool that can be used to display work in the form of both Kanban boards and Gantt charts.



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View of the Maladière football stadium, the finish line of the cycle race, the public and the guest tent


The Tour de Romandie is a Swiss cycling stage race founded in 1947 that is considered as an ideal preparation for the Giro d’Italia and the Tour de France that take place later on.

The city of Neuchâtel hosted stages of the Tour de Romandie three times:

  • In 2011, arrival of the 3rd stage
  • In 2014, individual time-trial with a unique arrival on the grass of the Maladière soccer stadium
  • In 2019, prologue downtown Neuchâtel and departure of the 2nd stage

On each of these occasions, the city of Neuchâtel puts in place a local committee that is in charge of the organisation of the event in close collaboration with the authorities and the organization of the race.


  1. Member of the local committee, in charge of the planning and logistics of the stage.
  2. Participation to the coordination meetings with the authorities of the city of Neuchâtel.

Laurent Claude, Président du comité d’organisation local

In our various follies, in our desire to do and be different, the 2014 stage in particular will remain in the annals as something crazy! To be able to welcome the best cyclists in the world in a soccer stadium located above a shopping mall with the help of a ramp about a hundred meters long by breaking a traffic circle for a day … was a challenge that only our region, cradle of watchmaking, could imagine.

This unusual project could not have succeeded without Philippe’s help and experience in project management.

Some said: “They did it because they did not know it was impossible … ” to the impossible no one is held, it is enough to know how to surround oneself!

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Electric propulsion system installed in an aircraft


H55 is a Swiss company created in 2017 which mission is to bring tailored electric propulsion solutions to the aviation and VTOL industry.


  1. Support of the company during its startup phase with strategy and management tools.
  2. Support in project portfolio management.
  3. Project scheduling and monitoring.

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Philippe Lauper wearing an Auvernier Jazz Festival T-shirt on the festival site


The Auvernier Jazz Festival is an event that took place in an idyllic setting on the shores of Lake Neuchâtel from 2009 to 2021. An associative committee of about forty members and a hundred volunteers have enabled jazz music lovers to experience 11 editions alongside world-renowned artists, while tasting local products.


  1. Member of the committee, in charge of the logistics team (infrastructure, security, food & beverage, decoration, sustainable development).
  2. Management of the annual festival schedule.
  3. Partnership with the Auvernier Jazz Festival offering Prefix the opportunity to be visible in the communication of the festival and to welcome its clients in the VIP area of the festival.

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