An overview of prevention and correction methods for non-response in surveys

Sampling surveys are more than often affected by non-response. More so, the process of data collection is practically never free of non-response. Because of the damage that it has on survey estimates, taking measures of prevention and the treating for non-response it is clearly necessary. Considering the fact that non-response is a two-level phenomenon, i.e. item and unit non-response, the measures differ on the two types of non-response. The paper presents an overview of the methods used for prevention and control for item non-response and unit non-response.