160 страниц. 2014 год. LAP Lambert Academic Publishing Why do some students withhold their mental effort in learning or in performing academic tasks? Is this a learning problem or a motivation problem? This book aims to answer this question by analyzing how people's confidence judgement, levels of task expertise, and levels of task difficulty relate to their mental effort investment and task performance. A task performance model was proposed for testing and the contribution of this book is helpful for learning task design and human performance improvement.