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Rank CompanyGeneral Electric Cisco Systems Wal-Mart Stores Southwest Airlines Microsoft Home Depot Berkshire Hathaway Charles Schwab Intel Dell Computer Corp.

1 2 3 4 5 6 7 8 9 10

1. Descriptive statisticsOrganizing, summarizing and

presenting data in an informative way

-Graphically

or

-as averages

Price

Number Sold

$6

$5

$4

$3

$2

$1

10 20 30 40 50 600

Graphically:

Averages-The 2001 Honda Odyssey minivan averages 18 miles per gallon in city driving an 25 mpg highway driving-The average credit card debt for people who petitioned the US Bankruptcy Court on March 27, 2001 in Toledo, Ohio was $14,366 and the average medical debt was $8,086.- According to Consumer Reports, General Electric washing machine owners reported 9 problems per 100 machines during 2001. The statistic 9 describes the number of problems out of every 100 machines.

2. Inferential statisticsThe methods used to find out about a population based on a

samplePopulation- all possible individuals, objects, or measurements of interest

Sample- a portion of the population

Types of Statistics(examples of inferential statistics)

• EXAMPLE 1: TV networks constantly monitor the popularity of their programs by hiring Nielsen and other organizations to sample the preferences of TV viewers.

EXAMPLE 2: The accounting department of a large firm will select a sample of the invoices to check for accuracy for all the invoices of the company.EXAMPLE 3: Wine tasters sip a few drops of wine to make a decision with respect to all the wine waiting to be released for sale.

For each of the following, determine whether the group is a population or a sample.

1.The participants in a study of a new diabetes drug

2. The drivers who received a speeding ticket in Kansas City last month

3. Those on welfare in Cook County, Illinois.

4. The 30 stocks reported as part of the Dow Jones Industrial Average.

1. QualitativeNon-numeric

2. Quantitative

Reported numerically

Gender, major, home town

Test scores, ages, class enrollment

Classify each of the following as qualitative or quantitative:1. The weight of each member of a football team.

2. The month of birth of students.

3. Students’ scores on the 1st Statistics exam.

4. The Olympic track and field records.

5. The color of cars in the parking lot.

1. DiscreteUsually a gap between values

2. ContinuousAny value within a range

number of family members, student enrollment, cars in the parking lot

amount of snow in Lynchburg last winter, a person’s weight, tire pressure

Classify each of the following as continuous or discrete:1. The number of sit-ups

2. The acceleration of an automobile.

3. The number of pairs of shoes sold.

4. The temperature of this room.

5. The diving depth of a submarine.

1. Nominal levela.data is sorted into classes with no particular order

b.often non-numericc.Mutually exclusive

– only one category

- colors of M&Ms, cars

d. exhaustive

- each must appear in a category

2. Ordinal levela. data is ranked ( one category is higher than another)

- what could you be doing right now?b.Mutually exclusive

c. exhaustive

EXAMPLE: During a taste test of 4 soft drinks, Mountain Dew was ranked number 1, Sprite number 2, Seven-up number 3, and Orange Crush number 4.mutually exclusive – each is only in one categoryexhaustive – each has to be in one of the 4

3. Interval levela. data is ranked and the difference between values is a constant size.

- temperatures the last 3 days (zero degrees is no different than 95 degrees)

- test scores

b. Mutually exclusive – only 1 category or value

c. exhaustive – each value must be in a category

4. Ratio levela.a meaningful zero point

b.the ratio of two values is meaningfulweight, height and money

$20 vs $10 vs $0

Levels of Data

Nominal Data Ordinal Data Interval Data Ratio Data

Data may only be classified

Hair color, Zip code

Data is ranked

Order of finish, class

Meaningful difference

between values

temp, test score

Meaningful 0 point and ratio between values

Income, Distance to

class

Text, page 12

What is the level of measurement for each of the following variables?1.Student IQ ratings.

2. Distance students travel to class

3. Student scores on a statistics test

4. A classification of students by state of birth

5. A ranking of students by freshman, sophomore, junior, or senior

6. Number of hours students study per week.

What is the level of measurement for these items related to the newspaper business?

1.The number of papers sold each Sunday during 1998.

2. The number of employees in each of the departments, such as editorial, advertising, sports

3. A summary of the number of papers sold by county.

4. The number of years with the paper for each employee