Title: 
Headings: 

Content: Beside the existence of a model, other factors that have to be noted when selecting a descriptive research method are the target of the study and the nature of the activity to be studied. These come into surface especially in the following questions: Setting and disturbances. Many activities normally take place "in the field" in noisy environments where various factors which are not interesting in the study instigate variation in the activity and its recording. In order to avoid this disturbing variation you might wish to arrange the empirical study in a secluded room or laboratory, in the form of systematic observationor experiment. However, when weeding out possibly influential factors you should have at least an approximation of their effects on the activity, otherwise your observation will become biased in a way you cannot know. In that case it can be better to leave the activity to happen in its original setting and use non-systematic observation. Manipulation. The activity you wish to study is sometimes so infrequent that you perhaps will want to stimulate the object to initiate the activity to be studied, for example by asking people to start the activity. Indeed, manipulation is usual in systematic observationand in experiments.