For example, children do not always behave the same way with one parent as they do with the other parent, and animals do not behave the same way in zoos as they do in the wild. So, by sampling different situations, a researcher can make more objective observations than he would in only a specific situation. Having discussed ways to sample behaviour in research, we are now moving onto another issue, that is, what researchers should do to record behaviour as it occurs, that is, whether researchers are active or passive in recording behaviour. This refers to the methods of observation. Observational methods can be classified as "observation with intervention" or "observation without intervention". Observation with intervention can be made in at least two ways, participant observation and field experiment. In participant observation, observers, that is researchers, play a dual role: They observe people's behaviour and they participate actively in the situation they are observing. If individuals who are being observed know that the observer is present to collect information about their behaviour, this is undisguised participant observation. But in disguised participant observation, those who are being observed do not know that they are being observed.