1. Section 1.1 Getting Started
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Section 1.1
Getting Started

2. Statistics is the numerical description of sample data.
HAWKES LEARNING SYSTEMS
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Introduction to Statistics
1.1 Getting Started
Definitions:
Statistics is the science of gathering, describing, and analyzing data.
Statistics is the numerical description of sample data.

3. Data – information, in particular, information prepared for a study.
HAWKES LEARNING SYSTEMS
math courseware specialists
Introduction to Statistics
1.1 Getting Started
Definitions:
Data – information, in particular, information prepared for a study.
Population – a particular group of interest.
Parameter – a numerical description of a particular population characteristic.
Census – when data is collected from every member of the population.

4. Sample – a subset of the population from which data is collected.
HAWKES LEARNING SYSTEMS
math courseware specialists
Introduction to Statistics
1.1 Getting Started
Definitions:
Sample – a subset of the population from which data is collected.
Sample Statistic – a numerical description of a particular sample characteristic.

5. Group I want to know about Group I do know about
HAWKES LEARNING SYSTEMS
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Introduction to Statistics
1.1 Getting Started
Population
Sample
Whole group
Part of the group
Group I want to know about
Group I do know about
Characteristics are called parameters
Characteristics are called statistics
Parameters are generally unknown
Statistics are always known
Parameter is fixed
Statistics change with the sample

6. Population = all college students Sample = 359 college students
HAWKES LEARNING SYSTEMS
math courseware specialists
Introduction to Statistics
1.1 Getting Started
Identify the population and the sample.
In a survey, 359 college students were asked if they had tried Vanilla Coke. 83 said yes.
Population = all college students
Sample = 359 college students
A survey of 1125 households in the U.S. found that 65% subscribe to digital cable.
Population = all U.S. households
Sample = 1125 households

7. HAWKES LEARNING SYSTEMS
math courseware specialists
Introduction to Statistics
1.1 Getting Started
Is the numerical value a parameter or a statistic?
The average grade on Test 1 in Ms. Shirley’s statistics class is an 87.
Parameter
The average Math score for all high school graduates on the SAT was a 519.
In a survey of 135 college students, 52% of them said they plan to attend graduate school.
Statistic

8. Identify the population and sample.
HAWKES LEARNING SYSTEMS
math courseware specialists
Introduction to Statistics
1.1 Getting Started
The principal of a large K-12 school is considering adopting a dress code for the upcoming school year. Before going to the school board, he wants to know the percentage of parents who would favor a dress code. He randomly chooses 15 families from each grade to interview. Out of the 195 families surveyed, 76% favor a dress code.
Identify the population and sample.
Population = all families of the students at the school
Sample = 195 families
Does the value “76%” represent a parameter or a statistic?
Statistic

9. HAWKES LEARNING SYSTEMS
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Introduction to Statistics
1.1 Getting Started
Branches of Statistics:
Descriptive statistics – gathers, sorts, summarizes and displays the data; “just the facts”.
Inferential statistics – uses descriptive statistics to estimate population parameters; an educated guess about the population based on the facts.

10. HAWKES LEARNING SYSTEMS
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Introduction to Statistics
1.1 Getting Started
Identify the descriptive statistic(s). What inferences can be made?
In a survey of 100 students, 83.2% of students are happy with the food in the cafeteria.
Descriptive statistic: 83.2% of the 100 students surveyed are happy with the food in the cafeteria.
Possible inferences: 83.2% of all students are happy with the food in the cafeteria.

11. HAWKES LEARNING SYSTEMS
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Introduction to Statistics
1.1 Getting Started