# POLS 3650 Lecture Notes - Lecture 8: Simple Random Sample, Statistical Inference, Frequency Distribution

## Document Summary

Inferential statistics: calculations aimed at generalizing findings from our sample to the population. Statistics describing a sample are called point estimates. Statistics describing a population are called parameter values. Answer: inferential statistics involves measuring point estimates in our sample and drawing conclusions about parameter values in the population. Normality in frequency distributions: normal distributions are common for variables that take on many different values. Especially interval/ratio variable that describe characteristics of natural objects or organisms: of course, there are many such variables that are not normally distributed, too. Normaility in probability distributions: much like we can visualize the number of cases with specific values in a frequency distribution, we can visualize the probabilities of different outcomes in a probability distribution, theoretical probability. Probability calculated on the basis of theory. Probability is number of outcomes of interest divided by total number of possible outcomes: empirical probability. Probability calculated on the basis of empirical observation.