Learning, Unlearning and Re-learning Curves

Learning, Unlearning and Re-learning Curves (Volume IV of the Working Guides to Estimating & Forecasting series) focuses in on Learning Curves, and the various tried and tested models of Wright, Crawford, DeJong, Towill-Bevis and others. It explores the differences and similarities between the various models and examines the key properties that Estimators and Forecasters can exploit.

A discussion about Learning Curve Cost Drivers leads to the consideration of a little used but very powerful technique of Learning Curve modelling called Segmentation, which looks at an organisation’s complex learning curve as the product of multiple shallower learning curves. Perhaps the biggest benefit is that it simplifies the calculations in Microsoft Excel where there is a change in the rate of learning observed or expected. The same technique can be used to model and calibrate discontinuities in the learning process that result in setbacks and uplifts in time or cost. This technique is compared with other better known techniques such as Anderlohr’s.

Equivalent Unit Learning is another, relative new technique that can be used alongside traditional completed unit learning to give an early warning of changes in the rates of learning. Finally, a Learning Curve can be exploited to estimate the penalty of collaborative working across multiple partners. Supported by a wealth of figures and tables, this is a valuable resource for estimators, engineers, accountants, project risk specialists as well as students of cost engineering.

Alan Jones is Principal Consultant at Estimata Limited, an estimating consultancy service. He is a certified cost estimator/Analyst (US) and certified cost engineer (UK). Prior to setting up his own business he has enjoyed a 40 year career in the UK aerospace and defence industry as an Estimator; culminating in the role of Chief Estimator at BAE Systems. Alan has been a Challenge Panel Member at the Society of Cost Analysis and Forecasting (SCAF) and is Director and Accreditation Board Chairman at the Association of Cost Engineers.