Abstract
Context: Empirical studies have become a key tool in software engineering. One of the most used strategies when carrying out empirical studies is the one called Controlled Experiment. Additionally, motivation can be determinant for altering human behavior when participating in a controlled experiment. Aim: This study aims to analyse the influence of motivation by rewards in student subjects when participating in an experiment. Method: An exploratory study based on a mixture of empirical methods was conducted. This mixture consists of a Survey for understanding the optimum magnitud for a reward in case of participating in an experiment. And Finally, an Experiment was designed and executed for studying the effects of motivation in students when participating in an experiment. Results: The Survey results show that depending on the Experiment duration, students may need a reward in return to participate. In addition to this, the analysis of the driven Experiment suggests that motivation did not positively influence the results of the Experiment in terms of quality, time spent and productivity. Conclusions: Further research is needed to provide better knowledge about how motivation by reward can alter results in Experiments.