Classify each of the quadratic forms in Exercises 4148 as positive definite, positive semidefinite, negative definite, negative semidefinite, or indefinite.

Elementary Statistical Methods Notes: January 11-15, 2016 Chapter 1: Intro to Statistics Section 1.1 Statistics is the science of collecting, describing, and interpreting data. There are two types of Statistics: Descriptive Statistics (Chapters 2-4) Inferential Statistics (Chapters 8-11) (Chapters 5-7 cover probability) Chapter 5: Probability Chapter 6: Discrete probability distribution Chapter 7: Continuous probability distribution Descriptive Statistics includes the collection, presentation, and description of sample data (histograms, bar graphs, pie charts, etc…) Inferential Statistics consists of procedures to make inferences or conclusions about population characteristics from the info contained in the sample. A variable is a characteristic that changes or varies over time and/or for different individuals or objects under consideration (e.g. test scores, sales, etc…) Example: Body temperature is a variable that changes over time within a single person, it also varies from person to person. Data are observations (e.g. measurements) that have been collected. A population is the set of all individuals or objects or measurements whose properties are to be analyzed. A sample is a small part of the total population. A parameter is a numerical measurement describing some characteristics of an entire population. Example: The average age at time of admission for all students attending ECU *Greek letters are used to symbolize parameters: Mu = mean