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Frequent-flier programs : problems and pitfalls
Hu, Michael Y., (1988)
Natural mortality and participation fatigue as potential biases in diary panels : Impact of some demographic factors and behavioral characteristics on systematic attrition
Toh, Rex S., (1996)
Respondent non-cooperation in surveys and diaries: An analysis of item non-response and panel attrition
Lee, Eunkyu, (2004)