Statistical Sciences 2037A/B Lecture Notes - Standard Deviation, Statistical Hypothesis Testing, Confidence Interval
15 Jan 2013
School
Department
Professor
Document Summary
Chapter 19 diversity of samples from the same population. We collect samples from a population, measure the variable, answer the question, determine how close the answer from our sample is to the answer for the population. We need to understand the dissimilarity we see in various samples from the same population. With sample values we can make a good guess at what the population value is. In random samples we may not see the exact probability of a certain event. This is because probability is over the long run. The rule for sample proportions is standard deviation = sqrt(true proportion x [1-true proportion/sample size]). There is also a rule for what to expect from sample means. This is called the rule for sample means. It applies when the population of measurements is bell-shaped for any size sample measured and the population is not bell-shaped, but a sample size of at least 30 is measured.
