Naturalistic observation refers to the unstructured observation of a child in his/her natural environment.
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Naturalistic observation refers to a method in which the scientist tests hypotheses by observing people as they engage in everyday activities in their natural habitats (for example, at home, at school, or on the playground), technique in which people are observed as they behave spontaneously in some real-life situation
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Naturalistic observation refers to a type of observation in which a researcher observes behavior in a natural setting as unobtrusively as possible. Naturalistic observation is the process of watching without interfering as a phenomenon occurs in the natural environment; research method in which carefully planned observations are made in real-life settings.

Naturalistic observation is a research paradigm in which an observer observes participants in familiar, everyday contexts while ideally remaining as unobtrusive as possible; an approach to research in which the researcher engages in careful observation of behavior without intervening directly with the subjects.

Naturalistic observation is also known as Nonparticipant observation.