STAT 02260 Lecture 3: Statistics Chapter 2: Collecting data sensibly
2 Feb 2017
School
Department
Course
Professor
Document Summary
4 ways to get data!: published source: book, article, web, journal, survey: people survey and their responses are recorded, observational study: units are observed in natural setting, designed experiment: test different things in an experiment. Importance of sample selection: the probability of an observed sample will be. Representative sample: exhibits characteristics typical of those possessed by. Sampling: used to infer the characteristics of the sampled population the population of interest. Simple random sample: of n" experimental units is a sample selected from the population in such a way that every different sample of size n has an equal chance of its selection. Equation used to find the number of ways to choose m items from a distinct set of n items. Stratified random: often when population can be split into 2 or more groups. When groups differ widely on variable of interest. Quota: when there are specified # of sample points designated for each group of strata.
