| http://www.w3.org/ns/prov#value | - In our random digit???dialing survey, the weights arose from several sources, including differential selection (we selected all fatigued persons, but only a random subsample of nonfatigued persons) and adjustments for nonresponse in the process of identifying households, screening for fatigued individuals, and conducting interviews.19 Persons who completed a detailed interview received a base weig
|
