This dissertation investigated the stability, and adaptivity of decision making over time and under risk. Chapter 2 introduced a new method to measure the temporal discounting of money. Chapter 3 tested reduction invariance, and confirmed the validity of Prelec’s compound-invariant probability weighting function. Chapter 4 compared the deviations from constant discounting for health and money. Chapter 5 elicited people’s risk attitudes when using cash vs. numbers. Chapter 6 discussed if people have completely different risk preferences when making decisions from experience, and provided new evidence to the DFD-DFE gap literature.