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.