Lets get some things straight! * * * Introduction to Statistics Introduction: Necessary definitions Reference Text: The Practice of Statistics, Fourth Edition. Starnes, Yates, Moore Lesson 1.1.2

Welcome! This is just a short talk about some key terms. Since we are all going to be statisticians, we need to walk the walk, and talk the talk. Lesson 1.1.2

Why Do this? From Data Analysis to Inference Population Sample Collect data from a representative Sample... Make an Inference about the Population. Perform Data Analysis, keeping probability in mind…

Words to Know Individuals- are the objects described by a set of data. Individuals may be people, animals, or things. Examples: 30 dogs were surveyed for… 212 people were asked… 750,000 Honda Civics were tested for… Variable- is any characteristic of an individual. A variable can take different values for different individuals. Height : Inches, cm, meters Weight: pounds, grams, kilograms Color: red, orange, yellow, green, blue, purple, violet, indigo… Lesson 1.1.2

(Careful! Would you say zip codes are quantitative?) More words! Categorical Variable- places an individual into one of several groups or category. Examples: Single, married, divorced, widowed. Quantitative Variable-(#’s) takes numerical values for which it makes sense to find an average. Number of flips I can do Amount of candy bars I eat Amount of rain fall in a day/week/month/year (Careful! Would you say zip codes are quantitative?)

You Try! Categorize the following as categorical or quantitative? Major in college…………… # of units…………………… Type of Car………………… Earthquake magnitude…… # of earthquakes………….. Color of M&M’s……………. Amount of M&M’s………….

Answers Categorize the following as categorical or quantitative? Major in college…………… .....Categorical # of units…………………… …..Quantitative Type of Car………………… …..Categorical Earthquake magnitude……

Answers # of earthquakes………….. …..Quantitative Color of M&M’s……………. …..Categorical Amount of M&M’s………….

Last Word for now! Distribution- of a variable tells us what values the variable takes and how often it takes these values Basically this definition is a broad spectrum of what we will be covering in our year of statistics. This is for both categorical and quantitative data.

Why Do this? From Data Analysis to Inference Population Sample Collect data from a representative Sample... Make an Inference about the Population. Perform Data Analysis, keeping probability in mind…

Homework Get syllabus signed by parent and return for your Baca Buck. Prepare any and all supplies needed for this school year! Have your summer assignment ready to turn in next class. Lesson 1.1.2