Samples in which informants provide contact information about other people who share some of the characteristics necessary for a study
Systematically recorded information, whether numbers or labels, together with its context
A table in which data values are divided into either a "leaf" or a "stem." In a stem and leaf plot, the stem values appear on the vertical axis and the leaf values are listed on the horizontal axis.
Statistics law stating that a large number of items taken at random from a population will on the average have the population statistics