1. Notes 13-1 Basic Statistics
WARM-UP
Answer the following survey questions
Do you have a study hall?
How many states have you visited?
How many people live in your home?
Do you have internet access at home? 
How many hours of TV do you watch in a week?

2. I. Terms:
Statistics – branch of mathematics dealing with the collection, organization, analysis, and interpretation of information
Variable – characteristic of a person or thing which can be classified, counted, ordered or measured
C. Population – set of all individuals or objects you want to study
D. Sample – part of population actually studied

3. I. Terms: Data Qualitative: can be divided into categories
Bar graph, pie graphs, frequency tables
Quantitative: numerical
Discrete
Continuous
Describe shape, center and spread
Stem plot, box plot, histogram

4. II. Graphs for Qualitative data:
Bar Graphs
Used to compare
Equal intervals and equal widths
Circle Graphs
Used to show parts of whole
Best when data consisting of a sum and component parts
Must calculate
measure of central
angle corresponding
to part of sum .

5. II. Graphs for Quantitative Data
Stem plots
Used to describe small data sets
Must have a key
Histogram
Used for larger set of data to see distribution
Continuous bars with equal intervals
Box Plot
Divides data into 4 quartiles
Used to show center & spread of data

6. III. Distribution Shape
Symmetric: Right and left sides of the distribution have frequencies that are mirror images of each other.
Uniform: All data values are approximately the same frequency

7. III. Distribution Shape
Skewed left: Left side of the distribution has much lower frequencies than the right.
Skewed right: Right side of the distribution has much lower frequencies than the left

8. IV. Examples: Identify the data as either qualitative or quantitative.
Number of questions answered correctly on a true-false test.
Weight of each animal in a zoo
Person’s blood type

9. IV. Examples:
A class of 25 students took a math test. Of these, 4 earned A’s, 11 earned B’s, 7 earned C’s, and 3 earned D’s. Create a table with frequencies and relative frequencies for each grade

10. IV. Examples
From the four Common Distribution Shapes, choose the best distribution for the data.
Ages of people in an elementary school
Age at death for all people in the United States
IQ scores of all men in United States