ABSTRACT
An experiment has great advantages for studying relationships. In this chapter, the authors take up the special places of the two methods for studying processes that develop only over a period of time. They discuss the panel method as a device for studying changes over time. The main drawback of the time-series method is that it is vulnerable to changes in general conditions that may be relevant to the phenomenon the researcher want to study. Geographical differences were the core of R. Cavan’s cross-sectional study of suicide and anomie. C. Mills made a fascinating study of three small cities that had each come to be dominated by one or a few big businesses and of three matched small cities in which smaller businesses mainly supported the local economies. The obvious way to study changes over time is to obtain a sample of the subject matter and actually to watch its change.
