The researcher keeps their real identity and purpose secret from the research subjects. If participating, they usually pose as a genuine member of the group
Interpretivists seek to discover the meanings that underlie our actions and this means using open-ended methods that produce valid, qualitative data. They find PO an effective way of uncovering people's meanings. Sustained participation in a group's activities allows the observer to gain a clear understanding of their worldview that can be constantly checked against their daily experience of the group. The researcher sees what people actually do, not what they may say they do.
PO lacks reliability and representativeness, but interpretivists are more interested in validity and they see PO as the technique that gets closest to this aim
Uses an observation schedule to identify and measure patterns of behaviour. The researcher decides in advance how to categorise the behaviour they will observe. The categories on the schedule are coded so that the data collected can be easily counted and turned into statistics.
Positivists argue that there is a measurable, objective social reality 'out there'. They take a scientific approach using standardised methods of research to obtain quantitative data that allows them to produce generalisations and cause-and-effect statements. Positivists prefer to use structured observation because it uses fixed categories and so observations can be easily quantified.