SWK 491 Lecture 2: 10/4/18
Document Summary
Population (55): the whole group or set of individuals/objects to be studied. Sample (20): smaller subset of a population, what we actually study. Creating an accurate sample size is the difficult portion of using a population in a study. Probability sample: one in which everybody in the population has an equal chance/possibility of being a part of the sample. Sampling error: how accurate/inaccurate the sample represents the population. Simple random sampling example: close your eyes and choose 20 random m&ms. Outlier: an element that is much higher or lower than the average. \ Systematic random sample: somewhat random with a method of choosing. Nth member (element) of a population to include the sample. Stratified random sample: choosing elements from predetermined subsets of a population. Srs sample of 20 (proportionate, random choosing from each category): Disproportional: could be overweighting or underweighting a srs sample.
