Methods and apparatus to monitor shoppers in a retail environment are disclosed herein. In a disclosed example method involves collecting location information indicative of a measured path of travel of a person through a monitored environment. The example method also involves collecting person detection event information associated with a plurality of zones in the monitored environment. The person detection event information is indicative of detections of the person in each of the zones. In addition, the example method involves determining an adjusted path of travel of the person through the monitored environment based on the location information indicative of the measured path of travel and the person detection event information.