Chapter One The Nature of Probability and Statistics

How can I do well in this class? Make sure you can do basic algebra. Attend all lectures. Complete all assignments. Go over answers to assignments. READ and STUDY the vocabulary. Form study groups with fellow students. Make sure you can use a calculator. HAVE FUN!!!

What Statistics is NOT Statistics is not math. –We use math to do statistics, but the emphasis is on interpretation.

Environment Agriculture, Ecology, Forestry, Animal Populations Government Census, Law, National Defense Physical Sciences Astronomy, Chemistry, Physics Areas where STATISTICS are used Health & Medicine Genetics, Clinical Trials, Epidemiology, Pharmacology Business Economics, Engineering, Marketing, Computer Science

What do statisticians do? Study the safety of nuclear power plants. Evaluate the impact of pollution. Determine the effectiveness of new drugs. Estimate the U.S. unemployment rate. Analyze consumer demand for products. Plan and analyze agricultural experiments.

What are Statistics? Statistics are particular calculations made from data. –Example: In this class there are 34 third year students. –This is data. 34% of this class are third year students. –This is a statistic.

What is Statistics? Statistics is the science of gaining information from data. –This is how stats touches all other subjects. We get our data from all other subjects: i.e. sociology, biology, engineering, economics, apparel and fashion merchandising, and more.

Vocabulary Knowing these will help you understand the problems. Cluster sample – randomly select a few clusters(e.g. geographic area, schools in a large district) Confounding Variable – influences outcome but cannot be separated (e.g. a study of the relationship between height and income) Continuous variable – infinite number between

Vocabulary Knowing these will help you understand the problems. Convenience sample Data – values the variables can take on. Descriptive statistics – collect, organize, summarize, and present data. Discrete variable – can be counted.

Vocabulary Knowing these will help you understand the problems. Experimental study – manipulation of a variable to see the effect on other variables. Inferential statistics – generalizing from samples to populations (relationships, estimations, and hypothesis tests). Observational study

Vocabulary Knowing these will help you understand the problems. Population – ALL subjects being studied. Qualitative variables – can be put in distinct categories. Quantitative variables – can be ordered or ranked (height, arm length). Random sample – chance methods or random numbers. Sample – group of subjects from pop.

Vocabulary Knowing these will help you understand the problems. Stratified sample – divide by characteristic and sample within strata. Systematic sample – number subjects and select every k th subject. Variable – characteristic or attribute that can assume different values. ∑ (means to add whatever is to the right of the symbol).