What is statistics: set of mathematical procedures for organizing, summarizing, and interpreting information. In other words : make sense of the numbers, large quantity of information. Interpret: compare summarized information, requires multiple sets of information, complicated manipulations and calculations, calculations built from summarized information, where research questions are answered, statistical tests that we will learn about. The subjects: the population, set of all individuals of interest in a study, defined by the research question, usually impossible to examine entire population, the sample, set of individuals selected from a population to represent that population. *remember!!: population parameter, p goes with p, sample statistic, s goes with s. The characteristics: sampling error, statistics do not perfectly represent parameters, discrepancy between a parameter and a statistic, error can be systematic or unsystematic, something causes a difference vs. random chance. Type of variables/data: categorical (discrete, separate categories, no values between categories, continuous. Interval: ordered categories, no meaningful zero point.