Holger A. Rau
Real-Effort Task: Minimzing Learning Behavior

Volker Benndorf, Christian Sölch and me developed a new real-effort task to conduct economic experiments.
The main goal is to provide a powerful real-effort task  for repeated real-effort experiments. Therefore, it intends
to mitigate subjects' learning behavior in doing the task.

The task builds on the word-encryption task of Erkal et al. (2011). In the task, subjects are presented words and a grid which allocates numbers
to the letters. The goal is to encrypt the words with the allocated numbers. We extended this task in several features. To complicate it
we only use three-letter combinations of non-existing words. Most importantly, we applied a double-randomization mechanism.
The idea is that the allocation table is shuffled whenever subjects made correct inputs. First, the table shuffles the letter-number allocation.
Second, it shuffles the positions of the letters.
Existing experiments using repeated real-effort tasks report an increase of 15-30% in subjects’ performance in the course of the experiment.
By contrast, we find that when comparing performance in the first period with the last period, our task mitigates learning behavior down to 8%.
The difference between the first and second half of the experiment is only about 3%.

Below, you find a screen shot of the task. Furthermore we provide you with the z-Tree code

Download the task

Cite task as follows: Benndorf, V., Rau, H.A., and Sölch, C. (2014), Minimizing Learning Behavior in Experiments with Repeated Real-Effort Tasks.
Working Paper, available at SSRN: http://ssrn.com/abstract=2503029




Dr. Holger A. Rau

Assistant Professor of
Experimental Economics
E-Mail: holger.rau@uni-goettingen.de
web: http://www.uni-goettingen.de/rau

University of Göttingen
Platz der Göttinger Sieben 3
Room: 2.244 (Oeconomicum)
37073 Göttingen (Germany)
Fon: +49 (0)551 / 39-22281