Time of measurement

Measurements were made at intervals of 10 seconds during the sessions of this study. The time of measurement is computed from its position within the session, the starting time of the session and the sampling interval (10 seconds). The starting time of the session time-series was taken from the session log sheet.

The start time of the session used in computing the time of measurement is taken from the the log sheet. The time on the log sheet was taken from the volunteers watch at the time the EMDEX data collection was begun. The times from the log sheet are recorded to the nearest minute. All times from the log sheet are relative to the volunteer's watch. Some times were estimated from the volunteer's memory, in cases where location changes were not immediately recorded. The difference between the EMDEX internal clock, which determines the true sampling interval, and the watch time is not thought to be significant for the period of interest.