“10 years on average doesn’t mean 10 years in any case” –an Experimental Investigation of People’s Understanding

of Fixed and Continuous Delays

Andreas Größler, Inge Bleijenbergh, Jac Vennix*

* Radboud University Nijmegen, the Netherlands, {a.groessler, i.bleijenbergh, j.vennix}@fm.ru.nl

The purpose of the paper is to test whether people make different decisions when a

dynamic task requires either a fixed delay or a continuous delay representation. We

assume that people have a tendency to cognitively represent continuous delays in real

life situations as fixed delays. With the help of a structurally simple dynamic decision

making task, we test two conditions in a controlled experiment: hiring when personnel

stays in an organisation for exactly ten years (fixed delay condition) or when personnel

stays on average for ten years (continuous delay condition). In this preliminary study,

71 participants were tested. Findings so far show no differences in performance

between the groups, indicating that they most likely use the same cognitive

representation of the task. Since participants’ answers are substantially closer to the

fixed delay condition, we assume that people have the tendency to represent lags in

the form of discrete delays, at least in the context of personnel hiring. Research

implications comprise the repetition of the experiment to achieve a higher number of

participants and to allow for a more extreme differentiation between the two conditions.

Practical implications regard the formulation of decision making tasks within

organisations, for instance in human resource management. The value of this paper

lies in its rigorous usage of a structurally simple dynamic task to shed light on a

fundamental trait of human decision making.

Discrete vs. continuous delays Task structure

Estimations of all participants Average error for experimental groups

32%

41%

27%outside bounds (% < 50 or > 100)

wrong estimate (diff. > 5 years)

correct estimate (diff. <= 5 years)

Male

professors

Female

professors

hiring males

hiring females

leaving males

leaving females

avg time at

universitypercentage females

hirings necessary

Ini Male

Ini Female

0

1

2

3

4

5

6

7

8

9

discrete continuous

years

x x

to t* t to t* t

input system response