Studies you should know: Like most things in psychology, free time follows a similar idea
A study by M. Sharif, C. Mogilner, and H. Hershfield on time and subjective wellbeing, published in the Journal of Personality and Social Psychology.
Studies you should know: The benefits of a psychologically rich life
A study by S. Oishi and E. Westgate on happiness, meaning, and a psychologically rich life, published in Psychological Review.