Biology 2244A/B Study Guide - Midterm Guide: Randomized Experiment, Statistical Inference, Confidence Interval

• School: Western University
• Department: Biology
• Course: Biology 2244A/B
• Professor: Jennifer Waugh

Document Summary

All normal distributions are the same if we measure in units of size (sigma) about the mean (mu) as center: changing these units is called standardizing. Z-score tells us how many standard deviations the original observation falls away from the mean. Observations larger than the mean are positive when standardized and observations smaller than the mean are negative. If the variable we standardize has a normal distribution, standardizing does more than give a common scale: makes all normal distributions into a single distribution and this distribution is. Standardizing a variable that has any normal distribution produces a new variable that has the standard normal distribution. Areas under a normal curve represent proportions (frequencies) of observations from that. Normal distributions: also represent probabilities of randomly selecting an individual from that normal distribution. To use a table to find cumulative proportions we must first standardize to express the problem in the standard scale of z-scores. Table of standard normal probabilities with z-score.