Used interchangeably with theoretical sampling since the only difference between the two is that purpose behind purposive sampling is not theoretically defined
A technique in which the researcher employs explicitly formulated rules for the observation and recording of behavior
The rules have observation schedule used to ensure that each participant's behavior is systematically recorded so that it is possible to aggregate the behavior of all samples in respect to each type of behavior being recorded
Prolonged immersion of the observer in the social setting where he/she seeks to observe the behavior of members in the setting (group, organization, community, etc)
Opportunity to actively engage with research material from the beginning, awareness of own impact on data, enhancing validity of data gathering techniques
Social attributes (race, ethnicity, nationality, gender, religion or sexual preferences) can affect positions and relations of power and authority in the research process