The level of motivation of the participants in the study is measured by a conscientiousness
scale from a subset of the Personality Characteristics Inventory developed by Barrick and Mount
(1991).11 Research has shown this measurement to reflect traits ‘‘such as hardworking,
achievement-oriented, and persevering,’’ which are directly related to task performance (Barrick
and Mount 1991, 4). Some previous research has measured motivation by the time spent
completing the research task; however, time represents a controversial proxy for motivation.
Further, in this study the instrument is not administered in a lab setting, so assessing motivation as a
self-reported measure of the time spent completing the tasks is a relatively unreliable proxy. Thus,
in this study, a measure of the conscientiousness or ‘‘will to achieve’’ of the individual participants
is used as a proxy for individual participants’ motivation