ABSTRACT
Researchers frequently draw a sample from a population, which is the group in which researchers are ultimately interested. A population may be large, such as all social workers in the United States, or small, such as all social workers employed by a specific hospital. If a researcher studies every member of a population, the researcher is conducting a census. For large populations, however, it is more efficient to study a sample instead of conducting a census. After drawing a sample, researchers study it and then make inferences to the population. That is, researchers infer that the characteristics of the sample probably are the characteristics of the population.1
