CHAPTER 1—DATA AND STATISTICS

MULTIPLE CHOICE

	1.	Methods for developing useful decision-making information from large data bases is known as
a.	data manipulation	
b.	data monitoring	
c.	data base conversion	
d.	data mining	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

	2.	The process of capturing, storing, and maintaining data is known as
a.	data manipulation	
b.	data monitoring	
c.	data warehousing	
d.	category analysis	

ANS:	C	PTS:	1	TOP:	Descriptive Statistics	

	3.	The subject of data mining deals with 
a.	methods for developing useful decision-making information from large data bases	
b.	keeping data secure so that unauthorized individuals cannot access the data	
c.	computational procedure for data analysis	
d.	computing the average for data	

ANS:	A	PTS:	1	TOP:	Descriptive Statistics	

	4.	In a questionnaire, respondents are asked to mark their gender as male or female. Gender is an example of the
a.	ordinal scale	
b.	nominal scale	
c.	ratio scale	
d.	interval scale	

ANS:	B	PTS:	1	TOP:	Descriptive Statistics	

	5.	The nominal scale of measurement has the properties of the
a.	ordinal scale	
b.	only interval scale	
c.	ratio scale	
d.	None of these alternatives is correct.	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

	6.	The scale of measurement that is used to rank order the observation for a variable is called the
a.	ratio scale	
b.	ordinal scale	
c.	nominal scale	
d.	interval scale	

ANS:	B	PTS:	1	TOP:	Descriptive Statistics	

	7.	Some hotels ask their guests to rate the hotel's services as excellent, very good, good, and poor. This is an example of the
a.	ordinal scale	
b.	ratio scale	
c.	nominal scale	
d.	interval scale	

ANS:	A	PTS:	1	TOP:	Descriptive Statistics	

	8.	The ordinal scale of measurement has the properties of the
a.	ratio scale	
b.	interval scale	
c.	nominal scale	
d.	ratio and interval scales	

ANS:	C	PTS:	1	TOP:	Descriptive Statistics	

	9.	The ratio scale of measurement has the properties of
a.	only the ordinal scale	
b.	only the nominal scale	
c.	the rank scale	
d.	the interval scale	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

	10.	Temperature is an example of a variable that uses
a.	the ratio scale	
b.	the interval scale	
c.	the ordinal scale	
d.	either the ratio or the ordinal scale	

ANS:	B	PTS:	1	TOP:	Descriptive Statistics	

	11.	The interval scale of measurement has the properties of the
a.	ratio and nominal scales	
b.	ratio and ordinal scales	
c.	ratio scale	
d.	None of these alternatives is correct.	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

	12.	Arithmetic operations are inappropriate for
a.	the ratio scale	
b.	the interval scale	
c.	both the ratio and interval scales	
d.	the nominal scale	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

	13.	Income is an example of a variable that uses the
a.	ratio scale	
b.	interval scale	
c.	nominal scale	
d.	ordinal scale	

ANS:	A	PTS:	1	TOP:	Descriptive Statistics	

	14.	Data obtained from a nominal scale
a.	must be alphabetic	
b.	can be either numeric or nonnumeric	
c.	must be numeric	
d.	must rank order the data	

ANS:	B	PTS:	1	TOP:	Descriptive Statistics	

	15.	The scale of measurement that has an inherent zero value defined is the
a.	ratio scale	
b.	nominal scale	
c.	ordinal scale	
d.	interval scale	

ANS:	A	PTS:	1	TOP:	Descriptive Statistics	

	16.	Arithmetic operations are appropriate for
a.	only the ratio scale	
b.	only the interval scale	
c.	the nominal scale	
d.	None of these alternatives is correct.	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

	17.	Quantitative data refers to data obtained with a(n)
a.	ordinal scale	
b.	nominal scale	
c.	either interval or ratio scale	
d.	only interval scale	

ANS:	C	PTS:	1	TOP:	Descriptive Statistics	

	18.	Data
a.	are always be numeric	
b.	are always nonnumeric	
c.	are the raw material of statistics	
d.	None of these alternatives is correct.	

ANS:	C	PTS:	1	TOP:	Descriptive Statistics	

	19.	The entities on which data are collected are
a.	elements	
b.	populations	
c.	samples	
d.	None of these alternatives is correct.	

ANS:	A	PTS:	1	TOP:	Descriptive Statistics	

	20.	The set of measurements collected for a particular element is (are) called
a.	variables	
b.	observations	
c.	samples	
d.	None of these alternatives is correct.	

ANS:	B	PTS:	1	TOP:	Descriptive Statistics	

	21.	A characteristic of interest for the elements is called a(n)
a.	sample	
b.	data set	
c.	variable	
d.	None of these alternatives is correct.	

ANS:	C	PTS:	1	TOP:	Descriptive Statistics	

	22.	All the data collected in a particular study are referred to as the
a.	inference	
b.	variable	
c.	data set	
d.	None of these alternatives is correct.	

ANS:	C	PTS:	1	TOP:	Descriptive Statistics	

	23.	Another name for "observations" is
a.	views	
b.	variables	
c.	cases	
d.	None of these alternatives is correct.	

ANS:	C	PTS:	1	TOP:	Descriptive Statistics	

	24.	Quantitative data
a.	are always nonnumeric	
b.	may be either numeric or nonnumeric	
c.	are always numeric	
d.	None of these alternatives is correct.	

ANS:	C	PTS:	1	TOP:	Descriptive Statistics	

	25.	In a questionnaire, respondents are asked to mark their gender as male or female. Gender is an example of a
a.	categorical variable	
b.	quantitative variable	
c.	categorical or quantitative variable, depending on how the respondents answered the question	
d.	None of these alternatives is correct.	

ANS:	A	PTS:	1	TOP:	Descriptive Statistics	

	26.	The number of cases will always be the same as the number of
a.	variables	
b.	elements	
c.	data sets	
d.	data	

ANS:	B	PTS:	1	TOP:	Descriptive Statistics	

	27.	Categorical data
a.	must be numeric	
b.	must be nonnumeric	
c.	cannot be numeric	
d.	may be either numeric or nonnumeric	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

	28.	Categorical data
a.	indicate either how much or how many	
b.	cannot be numeric	
c.	are labels used to identify attributes of elements	
d.	must be nonnumeric	

ANS:	C	PTS:	1	TOP:	Descriptive Statistics	

	29.	Ordinary arithmetic operations are meaningful
a.	only with categorical data	
b.	only with quantitative data	
c.	either with quantitative or categorical data	
d.	None of these alternatives is correct.	

ANS:	B	PTS:	1	TOP:	Descriptive Statistics	

	30.	Social security numbers consist of numeric values. Therefore, social security is an example of
a.	a quantitative variable	
b.	either a quantitative or a categorical variable	
c.	an exchange variable	
d.	a categorical variable	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

	31.	Temperature is an example of
a.	a categorical variable	
b.	a quantitative variable	
c.	either a quantitative or categorical variable	
d.	neither a quantitative nor categorical variable	

ANS:	B	PTS:	1	TOP:	Descriptive Statistics	

	32.	For ease of data entry into a university database, 1 denotes that the student is an undergraduate and 2 indicates that the student is a graduate student. In this case data are
a.	categorical	
b.	quantitative	
c.	either categorical or quantitative	
d.	neither categorical nor quantitative	

ANS:	A	PTS:	1	TOP:	Descriptive Statistics	

	33.	Arithmetic operations are inappropriate for
a.	categorical data	
b.	quantitative data	
c.	both categorical and quantitative data	
d.	large data sets	

ANS:	A	PTS:	1	TOP:	Descriptive Statistics	

	34.	Income is an example of
a.	categorical data	
b.	either categorical or quantitative data	
c.	dollar data	
d.	quantitative data	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

	35.	Data collected at the same, or approximately the same, point in time are
a.	time series data	
b.	approximate time series data	
c.	crossectional data	
d.	approximate data	

ANS:	C	PTS:	1	TOP:	Descriptive Statistics	

	36.	Data collected over several time periods are
a.	time series data	
b.	time controlled data	
c.	crossectional data	
d.	time crossectional data	

ANS:	A	PTS:	1	TOP:	Descriptive Statistics	

	37.	Statistical studies in which researchers do not control variables of interest are
a.	experimental studies	
b.	uncontrolled experimental studies	
c.	not of any value	
d.	observational studies	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

	38.	Statistical studies in which researchers control variables of interest are
a.	experimental studies	
b.	control observational studies	
c.	non-experimental studies	
d.	observational studies	

ANS:	A	PTS:	1	TOP:	Descriptive Statistics	

	39.	The summaries of data, which may be tabular, graphical, or numerical, are referred to as
a.	inferential statistics	
b.	descriptive statistics	
c.	statistical inference	
d.	report generation	

ANS:	B	PTS:	1	TOP:	Descriptive Statistics	

	40.	Statistical inference
a.	refers to the process of drawing inferences about the sample based on the characteristics of the population	
b.	is the same as descriptive statistics	
c.	is the process of drawing inferences about the population based on the information taken from the sample	
d.	is the same as a census	

ANS:	C	PTS:	1	TOP:	Descriptive Statistics	

	41.	The collection of all elements of interest in a particular study is
a.	the population	
b.	the sampling	
c.	statistical inference	
d.	descriptive statistics	

ANS:	A	PTS:	1	TOP:	Descriptive Statistics	

	42.	A portion of the population selected to represent the population is called
a.	statistical inference	
b.	descriptive statistics	
c.	a census	
d.	a sample	

ANS:	D	PTS:	1	TOP:	Statistical Inference	

	43.	In a sample of 800 students in a university, 240, or 30%, are Business majors. The 30% is an example of
a.	a sample	
b.	a population	
c.	statistical inference	
d.	descriptive statistics	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

	44.	In a sample of 400 students in a university, 80, or 20%, are Business majors. Based on the above information, the school's paper reported that "20% of all the students at the university are Business majors." This report is an example of
a.	a sample	
b.	a population	
c.	statistical inference	
d.	descriptive statistics	

ANS:	C	PTS:	1	TOP:	Descriptive Statistics	

	45.	Five hundred residents of a city are polled to obtain information on voting intentions in an upcoming city election. The five hundred residents in this study is an example of a(n)
a.	census	
b.	sample	
c.	observation	
d.	population	

ANS:	B	PTS:	1	TOP:	Descriptive Statistics	

	46.	A statistics professor asked students in a class their ages. On the basis of this information, the professor states that the average age of all the students in the university is 24 years. This is an example of
a.	a census	
b.	descriptive statistics	
c.	an experiment	
d.	statistical inference	

ANS:	D	PTS:	1	TOP:	Statistical Inference	

	47.	The owner of a factory regularly requests a graphical summary of all employees' salaries. The graphical summary of salaries is an example of
a.	a sample	
b.	descriptive statistics	
c.	statistical inference	
d.	an experiment	

ANS:	B	PTS:	1	TOP:	Descriptive Statistics	

	48.	The Department of Transportation of a city has noted that on the average there are 17 accidents per day. The average number of accidents is an example of
a.	descriptive statistics	
b.	statistical inference	
c.	a sample	
d.	a population	

ANS:	A	PTS:	1	TOP:	Statistical Inference	

	49.	The process of analyzing sample data in order to draw conclusions about the characteristics of a population is called
a.	descriptive statistics	
b.	statistical inference	
c.	data analysis	
d.	data summarization	

ANS:	B	PTS:	1	TOP:	Descriptive Statistics	

	50.	In a post office, the mailboxes are numbered from 1 to 4,500. These numbers represent
a.	categorical data	
b.	quantitative data	
c.	either categorical or quantitative data	
d.	since the numbers are sequential, the data is quantitative	

ANS:	A	PTS:	1	TOP:	Descriptive Statistics	

	51.	The average age in a sample of 190 students at City College is 22. As a result of this sample, it can be concluded that the average age of all the students at City College
a.	must be more than 22, since the population is always larger than the sample	
b.	must be less than 22, since the sample is only a part of the population	
c.	could not be 22	
d.	could be larger, smaller, or equal to 22	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

	52.	Since a sample is a subset of the population, the sample mean
a.	is always smaller than the mean of the population	
b.	is always larger than the mean of the population	
c.	must be equal to the mean of the population	
d.	can be larger, smaller, or equal to the mean of the population	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

	53.	The scale of measurement that is simply a label for the purpose of identifying the attribute of an element is the
a.	ratio scale	
b.	nominal scale	
c.	ordinal scale	
d.	interval scale	

ANS:	B	PTS:	1	TOP:	Descriptive Statistics	

	54.	In a data set, the number of elements will always be the same as the number of
a.	independent variables	
b.	observations	
c.	data points	
d.	dependent variables	

ANS:	B	PTS:	1	TOP:	Descriptive Statistics	

	55.	Which of the following is not a scale of measurement?
a.	nominal	
b.	ordinal	
c.	interval	
d.	primal	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

	56.	Which of the following is a scale of measurement?
a.	ratio	
b.	primal	
c.	divisional	
d.	remedial	

ANS:	A	PTS:	1	TOP:	Descriptive Statistics	

	57.	Which scale of measurement can be either numeric or nonnumeric?
a.	nominal	
b.	ratio	
c.	interval	
d.	None of these alternatives is correct.	

ANS:	A	PTS:	1	TOP:	Descriptive Statistics	

	58.	Which of the following variables use the ratio scale of measurement?
a.	social security number	
b.	temperature	
c.	gender	
d.	income	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

	59.	The weight of a candy bar in ounces is an example of
a.	categorical data	
b.	either categorical or quantitative data	
c.	weight data	
d.	quantitative data	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

	60.	The height of a building, measured in feet, is an example of
a.	categorical data	
b.	either categorical or quantitative data	
c.	feet data	
d.	quantitative data	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

	61.	An interviewer has made an error in recording the data. This type of error is known as
a.	an experimental error	
b.	a data acquisition error	
c.	a non-experimental error	
d.	a conglomerate error	

ANS:	B	PTS:	1	TOP:	Descriptive Statistics	

	62.	Census refers to
a.	an experimental study to collect data on the entire population	
b.	an experimental study to collect data on a sample	
c.	a survey to collect data on a sample	
d.	a survey to collect data on the entire population	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

	63.	In experimental studies, the variable of interest
a.	is not controlled	
b.	is controlled	
c.	must be numerical	
d.	cannot be numerical	

ANS:	B	PTS:	1	TOP:	Descriptive Statistics	

	64.	In observational studies, the variable of interest
a.	is not controlled	
b.	is controlled	
c.	must be numerical	
d.	cannot be numerical	

ANS:	A	PTS:	1	TOP:	Descriptive Statistics	

	65.	How many scales of measurement exist?
a.	1	
b.	2	
c.	3	
d.	4	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

	66.	Which of the following can be classified as quantitative data?
a.	interval and ordinal	
b.	ratio and ordinal	
c.	nominal and ordinal	
d.	interval and ratio	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

	67.	The sample size
a.	can be larger than the population size	
b.	is always smaller than the population size	
c.	can be larger or smaller than the population size	
d.	is always equal to the size of the population	

ANS:	B	PTS:	1	TOP:	Descriptive Statistics	

	68.	A population is
a.	the same as a sample	
b.	the selection of a random sample	
c.	the collection of all items of interest in a particular study	
d.	always the same size as the sample	

ANS:	C	PTS:	1	TOP:	Descriptive Statistics	

	69.	In a random sample of 200 items, 5 items were defective.  An estimate of the percentage of defective items in the population is
a.	5.0%	
b.	2.5%	
c.	200	
d.	10.0%	

ANS:	B	PTS:	1	TOP:	Descriptive Statistics	

	70.	On a street, the houses are numbered from 300 to 450.  The house numbers are examples of
a.	categorical data	
b.	quantitative data	
c.	both quantitative and categorical data	
d.	neither quantatative nor categorical data	

ANS:	A	PTS:	1	TOP:	Descriptive Statistics	

	71.	A survey to collect data on the entire population is
a.	a census	
b.	a sample	
c.	a population	
d.	an inference	

ANS:	A	PTS:	1	TOP:	Descriptive Statistics	

	72.	In Excel, a worksheet that displays the data for the problem and shows the results of the analysis is
a.	a formula worksheet	
b.	a value worksheet	
c.	an absolute worksheet	
d.	a descriptive worksheet	

ANS:	B	PTS:	1	TOP:	Descriptive Statistics	

	73.	In Excel, a worksheet that displays the formulas used to create the results is a
a.	results worksheet	
b.	formula worksheet	
c.	value worksheet	
d.	sample worksheet	

ANS:	B	PTS:	1	TOP:	Descriptive Statistics	

Exhibit 1-1
In a recent study based upon an inspection of 200 homes in Daisy City, 80 were found to violate one or more city codes.

	74.	Refer to Exhibit 1-1. The city manager released a statement that 40% of Daisy City's 2,000 homes are in violation of city codes. The manager's statement is an example of
a.	a census	
b.	an experiment	
c.	descriptive statistics	
d.	statistical inference	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

	75.	Refer to Exhibit 1-1. The Daisy City study described above is an example of the use of a
a.	census	
b.	sample	
c.	probability	
d.	population	

ANS:	B	PTS:	1	TOP:	Descriptive Statistics	

	76.	Refer to Exhibit 1-1. The manager's statement that 40% of Daisy City's 2,000 homes are in violation of city codes is
a.	an exactly correct statement	
b.	only an approximation, since it is based upon sample information	
c.	obviously wrong, since it is based upon a study of only 200 homes	
d.	None of these alternatives is correct.	

ANS:	B	PTS:	1	TOP:	Descriptive Statistics	

Exhibit 1-2
In a sample of 1,600 registered voters, 912, or 57%, approve of the way the President is doing his job.

	77.	Refer to Exhibit 1-2. The 57% approval is an example of
a.	a sample	
b.	descriptive statistics	
c.	statistical inference	
d.	a population	

ANS:	B	PTS:	1	TOP:	Descriptive Statistics	

	78.	Refer to Exhibit 1-2. A political pollster states: "Fifty-seven percent of all voters approve of the President." This statement is an example of
a.	a sample	
b.	descriptive statistics	
c.	statistical inference	
d.	a population	

ANS:	C	PTS:	1	TOP:	Descriptive Statistics	

Exhibit 1-3
Part of the data bank of a corporation is shown below.

Employee Number	Gender	Department	Years of Experience	Employee Rank (1 - 10)	Yearly Salary	
23450	Male 	Accounting	15	10	$  52,443.00 	
34568	Female	IT	24	7	$111,239.00 	
23123	Female	Personnel	20	4	$  84,473.00 	
23007	Male 	Finance	9	1	$  47,519.00 	

	79.	Refer to Exhibit 1-3.  Employee Number is an example of ________ data.
a.	nominal	
b.	ordinal	
c.	interval	
d.	ratio	

ANS:	A	PTS:	1	TOP:	Descriptive Statistics	

	80.	Refer to Exhibit 1-3.  Gender is an example of ________ data.
a.	nominal	
b.	ordinal	
c.	interval	
d.	ratio	

ANS:	A	PTS:	1	TOP:	Descriptive Statistics	

	81.	Refer to Exhibit 1-3.  Years of Experience is an example of ________ data.
a.	nominal	
b.	ordinal	
c.	interval	
d.	ratio	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

	82.	Refer to Exhibit 1-3.  Employee Rank is an example of ________ data.
a.	nominal	
b.	ordinal	
c.	interval	
d.	ratio	

ANS:	B	PTS:	1	TOP:	Descriptive Statistics	

	83.	Refer to Exhibit 1-3.  Yearly Salary is an example of ________ data.
a.	nominal	
b.	ordinal	
c.	interval	
d.	ratio	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

Exhibit 1-4

In many universities, students evaluate their professors by means of answering a questionnaire.  Assume a questionnaire is distributed to a class of 45 students.  Students are asked to answer the following:

1.  Sex
2.  Race (African descent, Caucasian, Other)
3.  Age
4.  Number of hours completed
5.  Grade point average
6.  My instructor is a very effective teacher

	84.	Refer to Exhibit 1-4.  How many elements are in the above data set?
a.	5	
b.	6	
c.	3	
d.	45	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

	85.	Refer to Exhibit 1-4.  How many variables are in this data set?
a.	3	
b.	4	
c.	5	
d.	6	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

	86.	Refer to Exhibit 4-1.  How many observations are in this data set?
a.	5	
b.	6	
c.	3	
d.	45	

ANS:	D	PTS:	1	TOP:	Descriptive Statistics	

PROBLEM

	1.	After graduation ceremonies at a university, six graduates were asked whether they were in favor of (identified by 1) or against (identified by 0) abortion. Some information about these graduates is shown below.

Graduate	Sex	Age	Abortion Issue	Class Rank	
Marissa	F	24	1	1	
Jason	M	22	1	2	
Wendy	F	41	0	3	
Edward	M	38	0	20	
Jennifer	F	25	1	4	
Tim	M	19	0	8	

a.	How many elements are in the data set?	
b.	How many variables are in the data set?	
c.	How many observations are in the data set?	
d.	Which of the above variables (Sex, Age, Abortion Issue, Class rank) are categorical and which are quantitative variables?	
e.	Are arithmetic operations appropriate for the variable "abortion issue"?	

ANS:	

a.	6	
b.	4	
c.	6	
d.	Sex: categorical	
	Age: quantitative	
	Abortion Issue: categorical	
	Class Rank: categorical	
e.	No	

PTS:	1	TOP:	Descriptive Statistics	

	2.	A recent issue of Fortune Magazine reported that the following companies had the lowest sales per employee among the Fortune 500 companies.

	Sales per Employee
(In $1,000s)	Sales
Rank	
Company			
Seagate Technology	42.20	285	
SSMC	42.19	414	
Russel	41.99	480	
Maxxam	40.88	485	
Dibrell Brothers	22.56	470	

a.	How many elements are in the above data set?	
b.	How many variables are in the above data set?	
c.	How many observations are in the above data set?	
d.	Name the variables and indicate whether they are categorical or quantitative.	

ANS:	

a.	5	
b.	2	
c.	5	
d.	Sales per employee: quantitative; Sales rank: categorical	

PTS:	1	TOP:	Descriptive Statistics	

	3.	The following shows the temperatures (high, low) and weather conditions in a given Sunday for some selected world cities. For the weather conditions, the following notations are used: c = clear; cl = cloudy; sh = showers; pc = partly cloudy.

City	Hi	Lo	Condition	
Acapulco	99	77	pc	
Bangkok	92	78	pc	
Mexico City	77	57	sh	
Montreal	72	56	pc	
Paris	77	58	c	
Rome	88	68	cl	
Toronto	78	61	c	

a.	How many elements are in this data set?	
b.	How many variables are in this data set?	
c.	How many observations are in this data set?	
d.	Name the variables and indicate whether they are categorical or quantitative.	
e.	For which variables are arithmetic operations appropriate and for which are they not appropriate?	

ANS:	

a.	7	
b.	3	
c.	7	
d.	Hi: quantitative, Lo: quantitative, Condition: categorical	
e.	Hi: appropriate, Lo: appropriate, Condition: not appropriate	

PTS:	1	TOP:	Descriptive Statistics	

	4.	The following data shows the yearly income distribution of a sample of 200 employees at MNM, Inc.

Yearly Income
(In $1,000s)	Number
of Employees	
20 - 24	2	
25 - 29	48	
30 - 34	60	
35 - 39	80	
40 - 44	10	

a.	What percentage of employees has yearly incomes of $35,000 or more?	
b.	Is the figure (percentage) that you computed in Part a an example of statistical inference? If no, what kind of statistics does it represent?	
c.	Based on this sample, the president of the company said that "45% of all our employees' yearly incomes are $35,000 or more." The president's statement represents what kind of statistics?	
d.	With the statement made in Part c, can we be assured that more than 45% of all employees' yearly incomes are at least $35,000? Explain.	
e.	What percentage of employees of the sample has yearly incomes of $29,000 or less?	
f.	How many variables are presented in the above data set?	
g.	The above data set represents the results of how many observations?	

ANS:	

a.	45%	
b.	No, it is descriptive statistics.	
c.	statistical inference	
d.	No, this is simply an inference and approximation based on the sample information.	
e.	25%	
f.	2	
g.	200	

PTS:	1	TOP:	Descriptive Statistics	

	5.	A recent issue of a national magazine reported that in a national public opinion survey conducted among 2,000 individuals, 56% were in favor of gun control, 40% opposed gun control, and 4% had no opinion on the subject.

a.	What is the sample in this survey?	
b.	Based on the sample, what percentage of the population would you think is in favor of gun control?	
c.	Based on the sample, what percentage of the population would you think have no opinion on the subject?	

ANS:	

a.	The 2000 individuals who were approached	
b.	56%	
c.	4%	

PTS:	1	TOP:	Descriptive Statistics	

	6.	The following table shows the starting salaries of a sample of recent business graduates.

Income (In $1,000s)	Number of Graduates	
15 - 19	40	
20 - 24	60	
25 - 29	80	
30 - 34	18	
35 - 39	2	

a.	What percentage of graduates in the sample had starting salaries of at least $30,000?	
b.	Of the graduates in the sample, what percentage had starting salaries of less than $25,000?	
c.	Based on this sample, what percentage of all business graduates do you estimate to have starting salaries of at least $20,000?	

ANS:	

a.	10%	
b.	50%	
c.	80%	

PTS:	1	TOP:	Descriptive Statistics	

	7.	Michael, Inc., a manufacturer of electric guitars, is a small firm with 50 employees. The table below shows the hourly wage distribution of the employees.

Hourly Wages (In Dollars)	Number of Employees	
10 - 13	8	
14 - 17	12	
18 - 21	20	
22 - 25	10	

a.	How many employees receive hourly wages of at least $18?	
b.	What percentage of the employees has hourly wages of at least $18?	
c.	What percentage of the employees has hourly wages of less than $14?	

ANS:	

a.	30	
b.	60%	
c.	16%	

PTS:	1	TOP:	Descriptive Statistics	

	8.	The following information regarding the top eight Fortune 500 companies was presented in an issue of Fortune Magazine.

	Sales
$ Millions	Sales
Rank	Profits
$ Millions	Profits
Rank	
Company					
General Motors	161,315	1	2,956	30	
Ford Motor	144,416	2	22,071	2	
Wal-Mart Stores	139,208	3	4,430	14	
Exxon	100,697	4	6,370	5	
General Electric	100,469	5	9,269	3	
Int'l Business Machines	81,667	6	6,328	6	
Citigroup	76,431	7	5,807	8	
Philip Morris	57,813	8	5,372	9	
Boeing	56,154	9	1,120	82	
AT&T	53,588	10	6,398	4	

a.	How many elements are in the above data set?	
b.	How many variables are in this data set?	
c.	How many observations are in this data set?	
d.	Which variables are categorical and which are quantitative variables?	
e.	What measurement scale is used for each variable?	

ANS:	

a.	10	
b.	4	
c.	10	
d.	Sales and Profits are quantitative	
	Sales Rank, and Profits Rank are categorical	
e.	Sales: ratio	
	Sales Rank: ordinal	
	Profits: ratio	
	Profits Rank: ordinal	

PTS:	1	TOP:	Descriptive Statistics	

	9.	The following information regarding a sample of seven students is provided.

Student	Identification number	Grade Point Average	Classification	Gender	Rank in Class	
Adam	1234	2.89	Senior	Male	15	
Brandon	8978	2.01	Junior	Male	25	
Jason	6578	3.97	Freshman	Male	3	
Marissa	2345	3.98	Sophomore	Female	2	
Michelle	8901	2.67	Senior	Female	18	
Wendy	7789	4.00	Senior	Female	1	
Webster	6780	3.77	Freshman	Male	4	

a.	How many elements are in the above data set?	
b.	How many variables are in this data set?	
c.	How many observations are in this data set?	
d.	Which variables are categorical and which are quantitative variables?	
e.	What measurement scale is used for each variable?	

ANS:	
a.	7	
b.	5	
c.	7	
d.	Grade point average is quantitative.  All others are categorical.	
e.	Identification Number:  nominal	
	Grade Point Average:  ratio		
	Classification:  ordinal	
	Gender:  nominal	
	Rank in Class:  ordinal	

PTS:	1	TOP:	Descriptive Statistics	

	10.	The following information regarding the ten richest Americans was reported in a recent issue of Forbes.

Name	Ranking	Worth
($Billions)	Age	Marital Status	Source	
Gates, William	1	59.0	51	married	Microsoft	
Buffett, Warren	2	52.0	77	married	Berkshire Hathaway	
Adelson, Sheldon	3	28.0	74	married	casinos, hotels	
Ellison, L. J.	4	26.0	63	married	Oracle	
Brin, Sergey	5	18.5	34	married	Google	
Page, Larry	5	18.5	34	single	Google	
Kerkorian, Kirk	7	18.0	90	divorced	investments, casinos	
Dell, Michael	8	17.2	42	married	Dell	
Koch, Charles	9	17.0	71	married	oil, commodities	
Koch, David	9	17.0	67	married	oil, commodities	

a.	How many elements are in the above data set?	
b.	How many variables are in this data set?	
c.	How many observations are in this data set?	
d.	Which variables are categorical and which are quantitative?	
e.	What measurement scale is used for each variable?	

ANS:	
a.	10	
b.	5	
c.	10	
d.	Worth and Age are quantitative	
	Ranking, Marital Status, and Source are categorical	
e.	Ranking:  ordinal	
	Worth:  ratio		
	Age:  ratio	
	Marital Status:  nominal	
	Source:  nominal	

PTS:	1	TOP:	Descriptive Statistics	

	11.	The following national weather report gives the temperatures and weather conditions on the previous day in cities across the nation.

	City	Hi	Lo	Condition	
					
	Albany, N.Y.	88	60	cloudy	
	Chicago	92	64	clear	
	Dallas-Ft.Worth	89	72	cloudy	
	Denver	75	54	clear	
	Hartford	88	61	cloudy	
	Honolulu	86	70	clear	
	Kansas City	93	74	clear	
	Los Angeles	80	62	cloudy	
	Nashville	94	72	rain	
	New York City	90	69	rain	
	Philadelphia	90	67	rain	

a.	How many elements are in this data set?	
b.	How many variables are in this data set?	
c.	How many observations are there in the above data set?	
d.	Which variables are categorical and which are quantitative?	
e.	What measurement scale is used for temperature and weather conditions?	

ANS:	
a.	11	
b.	3	
c.	11	
d.	Temperature is quantitative	
	Weather Condition is categorical	
e.	Temperature (Hi and Lo):  interval	
	Weather Condition:  nominal	

PTS:	1	TOP:	Descriptive Statistics	

	12.	The following table shows the age distribution of a sample of 180 students at a local college.

AGE DISTRIBUTION OF
180 STUDENTS AT A LOCAL COLLEGE

	Age of Students	Number of Students	
			
	15 - 19	  36	
	20 - 24	  44	
	25 - 29	  60	
	30 - 34	  38	
	35 - 39	    2	
		Total                    180	

a.	Of the students in the sample, what percentage is younger than 20 years of age?	
b.	What percentage is at least 30 years of age?	
c.	Based on this sample, what percentage of the students at the college do you estimate to be younger than 25 years of age?	

ANS:	
a.	20%	
b.	22.22%	
c.	44.44%	

PTS:	1	TOP:	Descriptive Statistics	

	13.	The highway patrol is interested in determining the average speed of automobiles traveling on I-75 between Chattanooga and Atlanta.  To accomplish this task, the speed of every tenth car passing a particular point on I-75 is recorded.

a.	What is the population for this study?	
b.	What constitutes the sample?	
c.	Is speed a categorical or a quantitative variable?	
d.	What type of measurement scale is used?	

ANS:	
a.	All the automobiles on I-75	
b.	All the tenth cars	
c.	quantitative	
d.	ratio	

PTS:	1	TOP:	Descriptive Statistics