We describe an instance-based model of decision-making for
repeated binary choice. The model provides an accurate
account of existing data of aggregate choice probabilities and
individual differences, as well as newly collected data on
learning and choice interdependency. In particular, the model
provides a general emergent account of the risk aversion
effect that does not require any metacognitive assumptions.
Advantages of the model include its simplicity, its
compatibility with previous models of choice and dynamic
control, and the strong constraints it inherits from the
underlying cognitive architecture.