Common Core Math IUnit 2 Day 1

One-Variable Statistics

Two Main Uses of Statistics

TO DESCRIBE(Data Analysis)

TO PREDICT(Statistical Inference)

Definitions

• Data: A collection of information in context.• Population: A set of individuals that we wish

to describe and/or make predictions about.• Sample: A subset of the population that data

is collected from.• Individual: Member of a population.• Variable: Characteristic recorded about each

individual in a data set.

Types of Variables

• Categorical Variable: A variable that records qualities or characteristics of an individual, such as gender or eye color.

• Quantitative Variable: A variable that measures a characteristic of an individual, such as height, weight, or age.

In this unit, we will focus on quantitative data.

What type is it?

Categorical Quantitative

Categorical or Quantitative Data?

• Birth month• Number of siblings• Height in inches• Average amount of time (in minutes) of your ride to

school.• Number of pets• Year & model of the car you drive• Age of your youngest parent• Predicted letter grade of your first Math 1 test.

1. Brand of vehicle purchased by a customer 2. Price of a CD 3. Number of students in a class of 30 who prefer peanut M&Ms over

plain M&Ms 4. Phone number of all the students enrolled in school. 5. The height of a 1 year old child.6. Number of students in a class of 35 who turn in a term paper before

the due date. 7. Gender of the next baby born at a particular hospital. 8. Amount of fluid (oz) dispensed by a machine used to fill bottles with

soda. 9. Thickness of the gelatin coating of a Vitamin C capsule10. Brand of computer purchased by a customer11. State of birth for someone born in the United States.12. Price of a textbook 13. The phone numbers of everyone in this class. 14. Actual weight of coffee in a one pound can.15. The length of a rattlesnake.

Describing Data

Two ways to describe data:• Graphically

• Numerically

• Dotplot

• Histogram

• Boxplot

Describing Data Graphically

Describing Data Numerically• Measures of Center –

mean, median

• Measures of Spread – range, interquartile range, standard deviation

Measures of CenterWhat is the typical value?

Measures of Spread

• Range

• Interquartile Range (IQR)

• Standard Deviation

How much do values typically vary from the center?

Common Core Math IUnit 2 Day 2

Frequency Tables and Histograms

Link Up

• Frequency Distribution Table• Histogram (by hand)

Describing Distributions

• Shape • Center

• Spread

• Outliers

Shape• Mound shaped &

symmetrical

• Skewed left (extreme low values)

• Skewed right (extreme high values)

• Uniform

Center

When describing a distribution at first, the center can be “eyeballed.”

Remember, you are trying to answer the question:“What is the most typical value?”

SpreadRange

Remember, you are trying to answer the question:“How much do values typically vary from the center?”

BE SURE TO STATE EVERYTHING IN CONTEXT!!

NFL Rushing Statistics

Group activity:• Make a frequency

distribution table for your assigned column of data.

• Draw the corresponding histogram on graph paper.

• Write a paragraph about your data that addresses shape, center, spread, and outliers.