Methods of Task Estimation

Methods for Estimating Task Duration.

At the planning stage of projects, it is imperative that attention is paid to estimation of task duration. This is because the entire project duration will be estimated from this activity. In other words, if the tasks durations are wrong, the estimated time of completion of the entire project will be wrong.

However, works in the entire project are broken down to tasks and each task is allotted time which is then aggregated to give an estimate of the entire duration of the project.

According to Wysocki (2009, p. 149) there are six methods of estimating task duration; similarity to other activities, historical data, expert advice, Delphi technique, Three-point technique, and Wide-band Delphi technique.

For this paper, I will consider the "Design of Independent Power Plant Station, Substations, Transmission Lines and Distribution lines for Asaritoru, Degema and Akokotoru Local Government Areas of Rivers State".

a) Similarity to other Activities

This is the process of using estimates of duration of similar activities of other jobs to estimate the duration of a present task this basically come from memory. Wysocki (2009, p. 149). We used this method in the estimation of task duration for the 132kv transmission lines as these were similar to 132kv transmission lines in the substation at Ukwa of Abia State works it was easy to adopt and come up with task durations.

b) Historical Data

In this method of estimation, past records of similar estimates are looked at to estimate duration for a task identified. Though this is similar to the one above, the difference is in the fact that this is gotten from the record bank unlike the other which seem to come basically from memory. Wysocki (2009, p. 149-150) This method is mostly in use in my establishment where we do a lot of repetitive works in the design of substations for example the substation in the project "rural electrification of Uwalor in Uromi Edo State" is similar to the ones in the "Independent Power Project at Asaritoru, Degemea and Akokotoru LGA and so we had to pick the task duration for this new project from the records in our library for the past designs.

c) Expert Advice

This process mainly had to do with estimating task that are new to you as a project manager. In this regard, it is wise to make use of the experience of others especially those outside your organization who are not your competitors any way. Wysocki (2009, p. 150). In applying this method of estimation in the estimation of task during for the pipelines, which are completely new to us as this project brought us into working with pipelines for the first time, we had to get advice from the Solar Turbine team carrying out works for the Shell Petroleum Development Company,