STATS 13 Lecture Notes - Lecture 1: Null Hypothesis, Standard Error, Alternative Hypothesis
Document Summary
Observation units: individual entities on which data are recorded. Variables: recorded characteristics of the observational units. Distribution of variable describes the pattern of value/ category outcomes. To measure the center of distribution find the average or mean. To measure variability, find the standard deviation. The standard deviation is the average distance between a data value and the mean. Sample size (n): the number of observational units. Simple random sample (srs): a random sample of observational units from a population. Statistic (random variable): numerical description or summary of the sample. A sample from a population is typically considered random. Do not change depending on the sample drawn. Sample mean and sample standard deviation are statistics. Population average - sum of all values in a population / # subjects. Z-test (normal test): observations are independent of one another. Testing proportions: at least 10 of each type of response is present in a sample.
