N (n)

The symbol(s) for SAMPLE size. Most social science research is carried out on samples from a POPULATION, rather than on the population itself. Whenever the DATA are from a sample, it is standard practice to report the sample size, such as N = 256, or n = 256. (There is no difference in practice between N and n, and each seems used about equally in the literature.) Furthermore, the reported N normally excludes cases with missing data on variables in the analysis. Thus, for example, a survey may have interviewed 1,000 respondents, but for the analysis of the six variables of interest, only 873 had no missing data, for an effective N = 873, not the original 1,000.