An analysis system analyzes a state of a person and includes a terminal configured to be worn on the person's body. The terminal includes an acceleration sensor, a storage unit, and a processing unit. The processing unit determines whether each value contained in the time series data is in a first state in which the value is equal to or greater than the threshold or in a second state in which the value is less than the threshold. The processing unit also determines a duration which is a period of time during which the first state continues. The processing unit quantifies a brain state of the person on the basis of the duration.