SWP 538 Lecture Notes - Lecture 8: Sampling Frame, Selection Bias, Internal Validity

• School: Ryerson University
• Department: Social Work
• Course: SWP 538
• Professor: Purnima George

Document Summary

Population= set of entities from which sample can be drawn to either describe subsection of population or generalize info to larger population. Sample= group of subjects (elements) selected from larger population. = hope that studying smaller group will reveal important things about larger group. Sampling frame= list of all elements or units containing the elements in population. Enumeration units= unit containing one or more units listed in sampling frame. Sampling unit= population selected for inclusion within sampling frame. Selecting a sample from larger population in which each member of population has equal chance of being selected for study. Occurs when subjects within experimental research design are placed into groups entirely by chance. Increases internal validity--- how confident researcher can be about intervention truly causing change in dependent variable instead of outside influences. Help reduce likelihood of bias because each subject has equal probability of being placed in each group.