# Sociology 2205A/B Study Guide - Final Guide: Scatter Plot, Association Football, Simple Random Sample

## Document Summary

Population: we choose a sample (carefully chosen subset of the population - representative) Epsn: (equal probability of selection method) - ensure representative sample. Sampling distribution def: distribution os statistics for all possible outcomes of a certain size. Mean (interval ratio) or proportion (nominal, ordinal) Links the sample stat to the population parameter giving us the theoretical number for pop. Statistics from random samples are used to estimate population parameters. Sampling error - size of con dence interval is the opposite. Ex between 12 and 18% had high school educations. Bias: unbiased if sample mean = population mean. Ef ciency: extent sample distribution is around the mean. (decrease sd by increasing sample size = more ef ciency) Larger sample size = closer to real population mean. Con dence level > z-score > con dence interval. Then divide alpha by 2* (use this . 025 to nd z-score using 3rd column)