Modeling and debiasing resource saving judgments

Ola Svenson
Nichel Gonzalez

Svenson (2011) showed that choices of one of two alternative productivity increases to save production resources (e.g., man-months) were biased. Judgments of resource savings following a speed increase from a low production speed linewere underestimated and following an increase of a high production speed line overestimated. The objective formula for computing savings includes differences between inverse speeds and this is intuitively very problematic for most people.The purpose of the present studies was to explore ways of ameliorating or eliminating the bias. Study 1 was a control study asking participants to increase the production speed of one production line to save the same amount of production resources(man-months) as was saved by a speed increase in a reference line. The increases judged to match the reference alternatives showed the same bias as in the earlier research on choices. In Study 2 the same task and problems were used as in Study 1,but the participants were asked first to judge the resource saving of the reference alternative in a pair of alternatives before they proceeded to the matching task. This weakened the average bias only slightly. In Study 3, the participants were askedto judge the resources saved from each of two successive increases of the same single production line (other than those of the matching task) before they continued to the matching problems. In this way a participant could realize that a secondproduction speed increase from a higher speed (e.g., from 40 to 60 items /man-month) gives less resource savings than the same speed increase from a first lower speed (e.g., from 20 to 40 items/man-month. Following this, the judgments of thesame problems as in the other studies improved and the bias decreased significantly but it did not disappear. To be able to make optimal decisions about productivity increases, people need information about the bias and/or reformulations of theproblems.



Cost Benefit Analysis (CBA) workshop in Stockholm

An open seminar and workshop in Stockholm will be held on 25-26 April 2018. The workshop deals with the use of CBA as a basis for decision-making in the public sector. The workshop is organized by, among others, Professor Jan-Eric Nilsson, VTI.



Ulf Sandberg has been presented with the TTI Lifetime Achievement Award 2018

VTI’s Senior Research Leader Ulf Sandberg has been presented with the TTI Lifetime Achievement Award 2018 for his work on research into tyres and road surface.


Steps need to be taken to increase traffic safety of automated cars

Several steps are necessary to ensure that automated and connected cars will lead to increased traffic safety – everything from ensuring that technology takes vulnerable road users into account, to new forms of driver training. This has emerged in a position...


FALCON examines challenges in the transport sector

VTI is one of several important partners in the major FALCON project*, whose purpose is to create knowledge and insight regarding the transport sector. In an initial subproject, VTI has produced a manual on transport, logistics and multimodality.


VTI joined research cooperation in China

In December 2017 VTI became a member of China-Sweden Research Centre for Traffic Safety (CTS).


Swedish German research collaboration on Electric Road Systems

The project “Swedish-German research collaboration on Electric Road Systems” (CollERS) has now officially started. The goal of the project is to increase the common knowledge around Electric Road Systems by cooperation between Germany and Sweden and to...


Electric Road Systems Conference 2018

After a successful first conference in June 2017, the Swedish research and innovation platform for electric roads is arranging the second dedicated International Conference on Electric Road Systems (ERS) June 13th and 14th 2018.