Direct Indirect and Human Mechanical Observation:

Direct Indirect Observation : In direct observation the behaviour of a person is observed. On the other hand indirect observation implies that same record of past behaviour is observed the behaviour is not observed and rather its effects are observed. Here the observer engaged in indirect observation generally looks for physical traces of behaviour or occurrence of an event.

Human Mechanical Observation : Here observation are done by manually or by machines. Most of the studies on marketing research are based on human observation where in trained observers are required to observe and faithfully record their observations. In some cases mechanical devices such as eye cameras and audiometers are used for observation. One of the major advantages of electrical mechanical devices is that their recordings are free from subjective bias. As against this advantage such observation may be less valid than human observations. This is because the observer power of integration can lead to a more valid evaluation of the observations.