Improving Estimation Quality with Psychology and Psychometrics

Here are some preliminary resources for our workshop.


Doing statistics in Excel is painful. For many people, though, there is no other choice. If you’re going to use Excel, download and install the Real Statistics Resource Pack available here.

As psychologists, we prefer to use the R programming language. You can download it here, and while you’re at it, download the RStudio development environment here.

Python is another programming language suitable for statistical analysis of estimation data. The fact that we currently provide no links here has nothing to do with our regard for the language, but only that we don’t know enough about it to provide proper download links.



Here are the slides to our presentation at the Scrum Gathering 2019 in Vienna.


Here is an Excel sheet that contain data that we tried to use for our work.

R scripts

Here is the RStudio project with our examples.


Here is the cognitive bias checklist.


Flyvbjerg, B. (2006) From Nobel Prize to Project Management: Getting Risks Right

Flyvbjerg, B. (2008) Curbing Optimism Bias and Strategic Misrepresentation in Planning: Reference Class Forecasting in Practice

Williams, L. et al.  (2011) Scrum + Engineering Practices: Experiences of Three Microsoft Teams

Other useful links

Greg Alleman’s page of estimation resources.

Erik Bernhardsson’s page of resources.

Ian Carroll’s page of resources.

This site will be updated whenever we find or produce new material.