Monitoring method and system

A system for identifying unusual activity in a monitoring space using a learning model, wherein the system: Monitors sensor activity timings for sensor activity measured by one or more sensors in the monitoring space during a first time period 510. Trains a probability model and obtains an activity probability threshold using the sensor activity timings measured in the first time period 512. Defines a threshold time or times for sensor activity based on the probability model and activity probability threshold. Monitors sensor activity measured by one or more sensors in the monitoring space during a second time period. Compares the sensor activity measured during the second time period with the threshold time or times to determine unusual activity 514. And raises an alert in response to determining unusual activity 516. Further aspects disclose processing and storing data, displaying activity information about a monitoring space, handling sensor data from a plurality of sensors in a monitoring space, and notifying a user of unusual activity.