Lesson 1-1Introduction to

StatisticsYou will learn to…* define statistics * define vocabulary associated with statistics

The word statistics is derived from the Latin word status, meaning

“state.”

3 reasons for studying statistics:

1) to understand results of studies done2) to be able to conduct our own research3) to become better consumers and citizens

Buying a car

Medicine

Source: Viagra.com

Car insurance

18 year old male$842.30

Car insurance

18 year old female$661.70

Car insurance

Stats in USC Colleges• Required• College of Arts and

Sciences – Science Departments

• Moore School of Business• College of Education – any

BS and Early Childhood• College of Engineering and

Information Technology• College of Pharmacy• Arnold School of Public

Health

• Optional• College of Arts

and Sciences – Arts Departments

• College of Education – any BA and Elementary

• School of Music

Sample Schedule USC School of Business

Third Semester• ECON 221 Principles of Microeconomics • MGSC 290 or Computers in Business or

MGSC 291 Probability and Statistics • MGMT 250/ENGL 463 or Professional

Communication or ENGL 282-286 Fiction, drama, poetry, or American or British literature

• ACCT 225 Introduction to Financial Accounting • Liberal Arts Philosophy, history, political

science, geography, foreign language, etc.

USC Nursing:General Education Requirements

• General education course selections must meet University general education requirements.

• English: ENGL 101-102 or higher• Social Sciences: Two courses from one of

these: sociology or psychology. One course must cover life-span content.

• Analytical Reasoning: To be satisfied in one of the following ways: 1) STAT 110 and MATH 122 or 2) STAT 110 and STAT 201

USC: Hotel Recreation Tourism Management

a. MATH 122 or 141, plus an additional course from PHIL 110 or 111, mathematics (at the next higher level), computer science (above CSCE 101), or statistics

b. Two courses from one of the following fields--Philosophy (110 and 111 only) or computer science (above CSCE 101) or statistics

Majors of USC Students in one STAT 110

Nursing

HRTM

Early childhood

Nursing

French/Pub Rels

Entertain. Mgt

Crim Just

Poli Sci & Cr J

Early childhood

Early childhood

Broadcast Jour

Nursing

HRTM

Poli Sci

Nursing

Jour/Mass Comm

Nursing

psych/premed

Business

Nursing

Broadcast Jour

Public Relations

Fashion Merch.

HRTM

Print Journalism

Crim Just

Early childhood

Broadcast Jour

Public Relations

What is Statistics?

Collect, Organize, Analyze, and Interpret Data

in order to Make Decisions

Statistics can be Hocus-Pocus!

What is data?

Data consists of information from observations, counts,

measurements, or responses.

examples: 5 ft, 98˚, 2 hrs, 165 lb, male, 50 years old, 4 fat grams, 200 times at bat, 100,000 sold

Population

The collection of all things being studied.

X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X XX X X X X X X X X X X X X X X X X X X X X X X X X X X

SampleA subset of the population.

Heights of Ridge View students

Heights of Ridge View students taking

probability & statistics

1. Population? All RV students

Heights of Ridge View students

Heights of Ridge View students taking

probability & statistics

2. Sample? RV prob & stats students

Population Sample

Time & Money

RV students RV seniors

all courses math courses

students in this class

students in this class

We get every measurement or count that is of

interest.

We may get only partial information,

but that might be the most economical way to get info.

Who was surveyed?university students

How many were surveyed?1746

Explain “At home: 82%.”82% of those surveyed like to

snack at home

Why do the percents add up to more than 100%?multiple answers were allowed

Who was surveyed?employed American adultsWho did the surveying?US Labor Department

Explain “Cashiers; 3,262,120; $5.75.”# of cashiers surveyed in 1996;

median hourly pay rate

The U.S. Department of Energy conducts a survey of 800

gasoline stations to determine the average price per gallon.

3. Identify the population.

4. Identify the sample.

5. What does the data set consist of ?

all gas stations

800 gas stations

price per gallon ($)

A study of 33,043 infants in Italy was conducted to find a link between a

heart rhythm abnormality and sudden infant death syndrome.

6. Identify the population.

7. Identify the sample.

8. What does the data set consist of ?

all infants

33,043 infants

heart rate in beats per minute

A survey of 546 women found that more than 56% are the job of

paying bills in their household.

9. Identify the population.

10. Identify the sample.

11. What does the data set consist of ?

all women

546 women

Yes or No – Are you the primary person in your household who pays the bills?

Parameter:A numerical description of a population.

Statistic:A numerical description of a sample.

P

* data from the population

S

* data from a sample

Parameter

12. The average income of all people in the U.S. in 2002.

13. The average income of people from three U.S. states in 2002.

Is the fact a parameter or statistic?

14. A survey of a sample of workers reported their starting salary

Statistic

Is the fact a parameter or statistic?

15. Starting salaries for the 2005 graduates from USC

16. The number of students with Cingular cell phone service in a random check of classrooms

Parameter Statistic

Parameter:A numerical description of a population.

Statistic:A numerical description of a sample.

P

* data from the population

S

* data from a sample

Parameters are fixed in value,while statistics vary in value.

Two Branches of Statistics

1) Descriptive Statistics

2) Inferential Statistics

* report the facts discovered in the survey

* use sample data to make conclusions about an

entire population* estimation, prediction, probability

POPULATION of women

N = 130,000,000

Whole Population AvailableFind the average height

of women 18 - 24

Collect Data

Describe Population

Descriptive

Statistics

POPULATION of women

N = 130,000,000

SAMPLE of women

n = 1000

Inferential

Statistics

Whole Population NOT AvailableFind the average height

of women 18 - 24

Collect Data

Use sample to estimate description

of population

Take Sample

17. 1000 U.S. teens were surveyed. 72% of the girls and 58% of the boys had after school jobs.

72% of the girls and 58% of the boys had after school jobs.

We predict that a higher percentage of teen girls have after school jobs.

Descriptive statistics:

Inferential statistics:

18. In a recent survey of 1000 adults, 47% said using a cell phone while driving should be illegal.

47% of 1000 U.S. adults believed that using a cell phone while driving should be illegal.

Based on a recent survey, about half of the population believe that using a cell phone while driving should be illegal.

Descriptive statistics:

Inferential statistics:

It’s Time to Practice!

Assignment 1.1

Lesson 1-2Types of Data

You will learn to…* classify data * identify types of measurements

Qualitative data

Examples:

Data that cannot be measured or counted

gender, favorite class, religious preference, eye color, hair color,

geographical location, zip code

characteristic or categorical

Quantitative data

Examples:age, heights, weights, temperatures, grades,

time, money

Data that can be measured or counted

numerical data

Qualitative or Quantitative data?

1. ID numbers of the students in this class

2. temperature each day this week

3. jersey numbers of the players on a team

4. vehicle models

qualitative

5. price of vehicles

quantitative

Nominal Data > list of categories, names, labels, or qualities

Examples: type of car you drive, your jersey number,

college you want to attend, eye color, hair color, gender, zip code

> order (rank) cannot be assigned to the categories

Ordinal Data> data that is ordered or ranked

Examples: race outcomes (1st,2nd,3rd), grade (A,B,C,D), top 5 sports teams, rating (good, better, best)

Decide whether the data is nominal or ordinal. Why?

1. highest level of education

2. marital status

3. zip code

nominal

4. rating for first impression of store

ordinal

Discrete Data > countable

Examples: number of courses you are taking, number of pairs of shoes you own,

number of CDs you own,score at figure-skating competition

cost of concert tickets

> usually integers only – no decimals or fractions

9.9, 9.5, 8.8, 10.0, 9.3

Continuous Data > not countable

Examples: weight of a bookbag,

minutes it takes for you to get to school, inches of rain fall

> weight or measurement

time is continuous

Decide whether the data is continuous or discrete. Why?

1. students wearing blue jeans

2. height of students

3. money each student has

discrete

4. weight of each bag of M&Mscontinuous

variable

qualitative

quantitative

nominal

ordinal

discrete

continuous

Lesson 1-3

StatisticalDesign

You will learn to…* identify ways to collect data * identify ways to get a sample of the population for a study

The goal of every study is to collect data and use it to

make a decision.

If the data collection process is flawed, then

the results are not valid.

Designing a Statistical Study

2) develop a plan for collecting data

1) identify data of interest & identify population

3) collect data

5) report inferential statistics

4) report descriptive statistics

6) identify any possible errors

Data Collection

1) Take a Census

2) Use a Sampling (entire population)

3) Create a Simulation (part of a population)

4) Conduct an Experiment

(reproduce conditions - crash dummies)

(study group & control group)

Which method of data collection?

1. the effect of changing flight patterns on the number of airplane accidents

2. the effect of aspirin on preventing heart attacks

simulation

experiment3. the weights of all linemen in the National Football League census

4. U.S. residents’ approval rating of the president sample

ExperimentEveryone in class will look at a

picture. Without saying anything, you will write down what you see

in the picture.

If you are sitting in seat 1-13, close your eyes, cover your eyes,

or put your head down.

Do not say anything.

Do not write anything.

Just look at the picture.

Without saying anything, write down

what you see in the picture.

Watch this video.In this video, 3 kids have white

shirts and 3 kids have black shirts. Focus on the kids in

white and count the number of times they pass the ball to a

different person.

When time and money prevent you from

collecting data from the entire population…

Data Collection

1) Take a Census

2) Use a Sampling (entire population)

3) Create a Simulation (part of a population)

4) Conduct an Experiment

(reproduce conditions - crash dummies)

(study group & control group)

5 Sampling Techniques (ways to choose a sample)

Random Sample:> Each member of the population has an equal chance of being selected.

(heights of students)

Using the Calculator

>MATH > PRB > randInt(

randInt (begin, end, # in sample)

randInt (1, # in population, # in sample)

How can we all get the same data?

1 rand

Stratified Sampling

> divide the population into groups using some characteristic

> select a few members from each group

Stratified Sampling

Low Income Middle

Income

High Income

X XX

X

X X

Stratified Sampling

A Hall

B HallC Hall

D Hall

Freshmen Sophomores

Juniors Seniors

Proportional Stratified Sampling

Low Income Middle

Income

High Income

2,000 families

500families

500 families

select 50 select 200

select 50

Cluster Sampling > population is divided into groups > use one group for the sample

Cluster Sampling

Low Income Middle

Income

High Income

Cluster Sampling Freshmen Sophomores

Juniors Seniors

Systematic Sampling

> every nth number from the population is included in the sample

Systematic Sampling

X X X

X X X

Choose every household 3rd

Systematic Sampling

Choose every 5th student

Convenience Sampling

> subjects used because they are convenient and available > volunteer sampling

* telephone survey

* survey at a shopping center

Identify the sampling technique used for each study.

5. select a class at random and question each student in the class

6. divide the students by grade level and question some students in each

grade level

cluster stratified

7. assign each student a number, generate random numbers, and question each student whose number is selected

Identify the sampling technique used for each study.

random

8. choose a starting point and question every 25th student

systematic

The commonly used sampling methods that often results in

biased samples are _______________________

• Volunteer sampling• Convenience sampling

The Statistical Process:

1) identify _________2) plan __________

3) collect & analyze ______

4) describe ______

5) make inferences about __________6) Identify possible ________

population

investigationdata

sample

populationerrors

It’s Practice Time!

Assignment 1.3

Ch 1 Review Assignment