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observer (ob-zer´ver)

One who perceives, notices, or watches; in behavioral research with humans, the investigator or his/her surrogate. [L. observo, to watch]
nonparticipant o. an investigator who studies a group of subjects engaged in certain activities but does not directly participate in these activities, presumably being able to study them more objectively.
participant o. an investigator who while studying the activities of a group of subjects also participates in their activities, presumably being able to gain more detailed, relevant information but with less objectivity.


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