Business Statistics
What is the Mean Absolute Deviation of the data set 7, 10, 14, and 20?
4.25
How many areas of the MS Excel interface were discussed in the video?
5
Which of the following are tools used in descriptive statistics?
Numerical Summaries Graphs and Charts
When is scientific notation useful?
When working with data sets that have a wide range of values
In Excel, in a formula, the character for computing the power of a number is ____.
^
A graph or table should have
a number a title
Discrete data can only take finite values.
true
In order to create a sample representative of the population, the analyst should use a _________ sampling technique.
random
Match the web address to the government bureau.
www.bls.gov: Bureau of Labor Statistics www.gpo.gov/erp :Economic Report of the President www.bea.gov: Bureau of Economic Analysis www.bjs.gov: Bureau of Justice Statistics
Which statement is correct?
Web searches (e.g., Google) often yield unverifiable data.
_________________ data are quantities that represent or track the values taken by a variable over equally spaced periods.
time series
True or false: A survey question might be discarded if too many responses are missing or flawed.
true
True or false: A survey question should avoid overlapping classes or unclear categories.
true
True or false: although non-random sampling techniques are considered less scientific than random techniques they are often used for expediency.
true
Samples are primarily
used to make inferences about population parameters. looking only at selected items from a population.
The ratio scale of measurement
uses the value zero as a meaningful value. can be used to measure cross-sectional and time series data. is the strongest, or most sophisticated, of the measurement scales.
A ___________survey provides information that the researcher wants.
valid/validity
Sample size is determined by the inherent _________ in the population of interest and the desired __________ of the parameter being estimated
variability, precision
A bar graph is ______________.
all of these options: a series of contiguous columns of varying heights to denote variations in data, an illustration of data points, a pictorial representation of statistical variations
According to the data in this video, which breed of dog is within one standard deviation of the mean height?
beagle
The best time to hire a statistical expert is at the __________ of a project
beginning/start
Statistics can appropriately be used for which of the following?
To handle too much or too little data. To communicate with people in technical fields. To better understand other people's data analysis.
collecting, organizing, and summarizing a particular data set are known as
descriptive statistics
_____________ or CRM is used by marketing departments to analyze customer data.
customer relationship management
To compute the standard deviation of a data sample ______________
Use STDEV.S
Which of the following are good reasons to hire a statistical consultant?
When a decision is faced with a public policy consequence. If you're at the beginning of a project and want advice on how to start. When your company lacks specific advanced skills.
A bar graph can have vertical or horizontal columns.
true
A sample set consists of randomly selected points from a population.
true
Hypothesis testing is about determining the likelihood of a population statistic being true.
true
Nominal data represent categories or labels, such as male and female.
true
Ordinal scale is an ordering of the nominal variables.
true
Simply stated, Histograms are a plot of data bins and the number of data points in each of them.
true
True or false: Successful businesses expect their employees to have some knowledge of statistics.
true
True or false: There are generally accepted statistical methods for dealing with missing data and unusual data.
true
Variables of type Ratio are the most complete
true
When there are an odd number of values in a distribution, the Median is the centrally located value when all the values are in ascending order.
true
You can choose which numbers to add/subtract/multiply/divide by selecting the cell.
true
A ________ is a subset of a population
sample
Which type of error is unavoidable when sampling from a population?
sampling error
Sampling, rather than surveying an entire population, can offer some substantial benefits. Some of those benefits include
saving money and time gaining information about a population of indefinite size.
Which of the following are examples of inferential statistics?
A manufacturer of light bulbs randomly selects 100 light bulbs to test the longevity of all light bulbs that the company produces. Prof. Stats randomly selects 50 female students at State University to estimate the average height of all female students at State.
Empirical data is data
collected through observation and experiment
"Lacrosse helmets are not needed," said Tom. "None of the guys on my team have ever had head injuries." Select the correct fallacy in Tom's reasoning?
conclusions from nonrandom samples
the type of statistics that refers to drawing conclusions about a population set of data based on a sample set of data is known as
inferential statistics
Business students need to study statistics because
it gives your company a competitive advantage if you know how to use and interpret data.
Which is not a reason for an average student to study statistics?
learn investment strategies
GM's experience with faulty ignition switches suggests that
limited data may still contain important clues.
In order to compute variance, _____ needs to be computed
mean
Given the null hypothesis that the mean height of Dobermans is 26 inches, an appropriate alternate hypothesis for this two-sided distribution will be ___.
mean height is not equal to 26 inches
In Excel, in a formula, the asterisk character (*) is used for ________.
multiplying two numbers
A recent study of 231,164 New Jersey heart attack patients showed that those admitted on a weekday had a 12.0 percent death rate in the next three years, compared with 12.9 percent for those admitted on a weekend. This difference was statistically significant. "That's too small to have any practical importance," said Sarah. Do you agree with Sarah's conclusion?
no
Is the set of all the footballs in the world a sample or population?
population
Which one has more data points?
population
A National Health Interview Survey conducted by the U.S. Centers for Disease Control and Prevention reported that using a cell phone instead of a landline appeared to double a person's chances of binge drinking. "I guess I'd better give up my cell phone," said Bob. Which fallacy, do you see in Bob's reasoning?
assuming a casual link generalization to individuals
A company code of ethics addresses things such as
sources of data inaccuracy policies on confidentiality conflicts of interest
________ is a set of tools which helps in organizing, presenting information, and extracting meaning from raw data.
statistics
The symbol ∑ is used to denote ___________
sum of data
Which is least likely to involve the application of statistics in business?
writing strategic decisions
Analysis of 1,064 deaths of famous popular musicians showed that 31 percent were related to alcohol or drug abuse. "But that is just a sample. It proves nothing," said Hannah. Do you agree with Hannah's conclusion?
yes
In the video example, what brand has the smallest sales, and how can we tell from the pie chart?
Lamborghini has the smallest sales, because its proportion of the pie is smallest.
Under a recent U.S. Food and Drug Administration (FDA) standard for food contaminants, 3.5 ounces of tomato sauce can have up to 30 fly eggs, and 11 ounces of wheat flour can contain 450 insect fragments. How could statistical sampling be used to see that these standards of food hygiene are being met by producers?
Sampling allows the FDA to state, within a margin of error and some level of confidence, that tomato sauce produced in the United States is meeting the standard.
A research study showed that 7 percent of "A" students smoke while nearly 50 percent of "D" students do. (a) If you are listing six factors in rank order that you think affect grades, is smoking on your list? (b) Assuming these statistics are correct, would "D" students who give up smoking improve their grades?
a) no b) no
_________ or CRM is used by marketing departments to analyze customer data.
customer relationship management
In this histogram, the height of a column is determined by the value of a student's test score
false
The Mean of a distribution is always a value from the distribution
false
True or false: Busy managers want to see detailed numerical explanations in technical reports.
false
True or false: Different assumptions will lead you to the same answer so it is not necessary to state your assumptions.
false
A research study showed that adolescents who watched more than 4 hours of TV per day were more than five times as likely to start smoking as those who watched less than 2 hours a day. The researchers speculate that TV actors' portrayals of smoking as personally and socially rewarding were an effective indirect method of tobacco promotion. List the factors that you think cause adolescents to start smoking.
friends smoking, seeing it on tv, wanting to look cool,
Which statistical pitfall does the following statements match? A college degree generally takes four years after high school is completed. Therefore Mary can complete her degree before she turns 22.
generalization to individuals
Match the business discipline to the type of data collected
identifying repeat customers: marketing A sample of errors from invoice statements: auditing Distribution of inventory items in a big box store: operations management risk assessment of an investment: finance
Which is not an analytical method commonly used to improve business decisions?
reactive analytics
One of the things you can do with the Status Bar is:
rename the tab
Where does one change the format of a cell, such as adding color or changing font style?
ribbon and worksheet area
It can be expensive or impossible to measure everything in a population so businesses often take a __________ to make predictions or estimates.
sample
There are ten sections of a math course at a university. One section is randomly chosen for a survey about calculator preferences. The group of students in this section is a ____.
sample
Ethical guidelines exist for
the treatment of humans and animals and privacy protection.
Which of the following are the responsibilities of a data analyst?
Identifying degrees of uncertainty Accurately reporting information Referencing sources
Statistics for a sample are denoted by ______
x̄, s2
The mean of a sample and standard deviation of a population are denoted by ______________
x̄, σ
Additional functions and their usage can be found in ___________
All of the options: "Lookup & Reference" tab within Formulas Help for Microsoft Excel
You can insert formulas by ______________
All of the options: Clicking on "Formulas" and then "Insert Function" Typing "=" and a function name If the "formula bar" is enabled in the view settings, typing directly in it
When you roll two dice, the data generated is ___
discrete
Measures of Central Tendency are representative of a central location in the distribution
True
Absolute deviations are _____________.
always positive
Statistical analysis is constrained by
lack of money to research. lack of time to collect data.
Which statistical pitfall does the following statement match? People who belong to health clubs tend to have college degrees therefore exercise increases your IQ.
Assuming a casual link
In the example shown, which brand of vehicles has the highest sales, and how can we tell?
Audi, because the bar representing its sales is longest.
Which is not a likely task of descriptive statistics?
Estimating unknown parameters
"Smokers are much more likely to speed, run red lights, and get involved in car accidents than nonsmokers." Can you think of reasons why this statement might be misleading? Can you suggest a causal link between smoking and car accidents?
"the phrase much more is not quantified", smokers might pay less attention to driving when lighting a cigarette
We have a number, 4.38E-02, in scientific notation. How would we represent it in non-scientific notation?
0.0438
Given the sample data set 4, 5, 6, what is the variance?
1
_______________ statistics involves collecting and summarizing data and ________________ statistics makes generalizations from samples to populations.
1. descriptive 2. inferential
_______ analytics look at historical data. ______ analytics are used to help make decisions about business objectives, and _________ analytics help forecast customer behavior.
1. descriptive 2. prescriptive 3. predictive
In scientific notation, the number 12,340,000,000 is represented in Excel as ____.
1.234E+10
In this data set, 1, 2, 3, 4, 4, the mode is
4
Which is not a practical constraint facing the business researcher or data analyst?
Survey respondents usually will tell the truth if well compensated.
Which statistical pitfall best matches the following statement match? Rebecca's dog was bitten by a snake while they were jogging. You should never take your dog jogging because they will be bitten by a snake.
conclusions from rare events
Match the type of statistics with the tasks:
descriptive: organizing graphing inferential: estimating concluding
In the video example, which dog breed has the largest variation?
doberman
Statistics allows us to test our ideas using __________.
empirical or sample evidence
We would associate the term inferential statistics with which task?
estimating unknown parameters
A pie chart is most useful to illustrate ______________.
proportions of the whole
When you measure the weight of a person, the data is ____.
continuous
Using data to develop models that forecast customer behavior would be
predictive analytics
Which of the following are rules for a data analyst?
Protect confidential information. Know and follow accepted procedures. Maintain data integrity.
XYZ Corporation made a profit of $3 million last year. ABC Corporation made a profit of $6 million last year. Based on the ratio scale, which of the following is an accurate statement about the relationship between ABC's profits and XYZ's profits?
XYZ was half as profitable as ABC.
knowing how to set a pricing strategy for rental cars would be an example of what type of analytics?
prescriptive
To compute the standard deviation, one _______.
takes the square root of variance
The Mean Absolute Deviation is _______________.
the average of all absolute deviations
If the brand that had most sales was Lamborghini, then ______________.
the bar (or column) corresponding to Lamborghini would be the largest
"Smoking is not harmful. My Aunt Harriet smoked, but lived to age 90." This best illustrates which fallacy is not illustrated,
small sample generalization
____________ sampling is often used for expediency.
nonrandom
Which publication was discontinued after 2012?
Statistical Abstract of the US
Data that are generally expressed with words, rather than numbers, are known as_________ variables.
categorical
The nominal scale of measurement is used to
categorize unranked data
Which is not a time series variable?
closing checkbook balances of 30 students on December 31 of this year
The General Accounting Office conducted random testing of retail gasoline pumps in Michigan, Missouri, Oregon, and Tennessee. The study concluded that 49 percent of gasoline pumps nationwide are mislabeled by more than one-half of an octane point. What kind of sampling technique was most likely to have been used in this study?
cluster sampling
Which method is likely to be used by a journalism student who is casually surveying opinions of students about the university's cafeteria food for an article that she is writing for publication tomorrow?
convenience sample
Identify which of the sampling techniques listed are non-random.
convenience, focus groups
Sample data can be characterized in different ways. Data that is collected about many subjects at the same point in time is known as ___________ data.
cross-sectional
An advantage of convenience samples over random samples is that
data collection cost is reduced
The sampling ________ is the group from which we take the sample.
frame
"Bob must be rich. He's a lawyer, and lawyers make lots of money." This statement best illustrates which fallacy?
generalizing from an average to an individual
A reliable survey is one that
gives consistent measurements.
The interval scale of measurement
has meaningful differences between values. does not have a meaningful zero point.
A Likert scale with an odd number of scale points between "Strongly Agree" and "Strongly Disagree"
is often used in marketing surveys
A multivariate data set contains
more than two variables
It can be difficult to ask a(n) ______ without any context in a survey.
neutral/unbiased
A significant weakness of the ordinal scale is
no clear meaning to differences between the ranked values.
What is a discrete variable?
the time it takes to put on a pair of jeans
Which of the following is not a likely reason for sampling?
the expense of obtaining tables of random numbers
Which of the following is not true?
the number of checks processed at a bank in a day is categorical data.
A pie chart is _______.
all of these options: a graph, an illustration of data points, a representation of numerical proportions
Below are five questions from a survey of MBA students. For each question, state the data type (categorical, discrete numerical, or continuous numerical) and measurement level (nominal, ordinal, interval, ratio). 1. On a 1 to 5 scale, assess the current job market for your undergraduate major. 1 = Very bad ↔ 5 = Very good 2. During the last month, how many times has your schedule been disrupted by car trouble? 3. About how many years of college does the more-educated one of your parents have? (years) 4. During the last year, how many traffic tickets (excluding parking) have you received? 5. Which political orientation most nearly fits you? (1 = Liberal, 2 = Middle-of-Road, 3 = Conservative)
1. categorical, ordinal/interval 2. discrete numerical, ratio 3. continuous numerical, ratio 4. discrete numerical, ratio 5. categorical, ordinal
Which of the following are examples of the interval scale of measurement?
A customer's satisfaction score Many Likert scales
Sampling is necessary when it is effectively impossible to survey the entire population. Which of the following situations illustrates a situation where sampling, rather than surveying the entire population, is necessary?
A manufacturer of automobile tires wants to determine how long the tread of its tires will last.
Which of the following statements is not correct?
A statistical test result that is significant also has practical importance.
Northern University's College of Business wants to determine the average starting salary for last year's graduates of its College of Business; what is the population that the College should survey from?
All of last year's graduates from Northern's College of Business.
Which of the following are examples of time series data?
Average annual credit card debt over the past decade The monthly Consumer Confidence Index for the past three years.
Match each type of variable in the left column with its corresponding example from the right column.
Categorical or Qualitative Diners at a restaurant are asked to rate the food based on the following scale, excellent, good, average, below average, poor. Discrete: The number of dots face up on the roll of a pair of dice. The number of dots face up on the roll of a pair of dice. Continuous: The finishing times for running the 100 meter dash.
Match sample and census with their corresponding features.
Census It is an examination of all items in a population. It is sometimes mandated by legal requirements. Sample It looks at only selected items in a population. It is necessitated because of budget constraints.
Which of the following are examples of the nominal scale?
Designating males as 1 and females as 2 to compare gender performance on an aptitude test Social security numbers Specialty sandwich names at a fast food restaurant
In sampling, _______ refers to over or underestimate a population parameter of interest.
bias/error
Which is most nearly correct regarding sampling error?
It cannot be eliminated by any statistical sampling method.
Match the survey types with their characteristics.
Mail: It requires a current mailing list. Telephone: It is undermined by distrust, call screening, and voicemail. Interviews: It is expensive and time-consuming but results are often high quality. Web: It is growing in popularity but needs a well-defined group, ideally on a question of self-interest.
Which of the following are problems that might arise with survey data?
Multiple responses Unusual replies on open-ended questions Inconsistent responses Missing data values
Identify whether the following are parameters or statistics.
Parameter: The average age of all students currently enrolled at the Leeds School of Business (population of interest is only current students.) Statistic: The average starting salary for 25 students from this year's Leeds' MBA graduating class (class has 110 graduates.)
Which of the following survey software is used in large enterprises such as universities?
Qualtrics
What are issues for consideration when designing a survey? Check all that apply.
Response Rate Time Required Training Required Cost
__________ is a commonly used free survey tool.
SURVEYMONKEY
-Which of the following characteristics of interest is a variable?
The number of pizzas ordered from Pizza Hut per day.
Which of the following is false?
The target population must first be defined by a full list or data file of all individuals.
Which of the following are examples of cross-sectional data?
The total hours worked last week by each employee at a factory. Last month's unemployment rate for various cities in Ohio. The hotel bill for each guest who stayed at a Holiday Inn on March 3rd.
The target population is all students in your university. You wish to estimate the average current Visa balance for each student. How large would the university student population have to be in order to be regarded as effectively infinite in each of the following samples? a. a sample of 10 students b. a sample of 50 students c. a sample of 100 students
a. 200 b. 1000 c. 2000 P = Sample x 20
Which measurement level (nominal, ordinal, interval, ratio) is each of the following variables? a. Number of passengers on Delta Flight 833. b. Waiting time (minutes) after gate pushback before Delta Flight 833 takes off. c. Brand of cell phone owned by a cabin attendant on Delta Flight 833. d. Ticket class (first, business, or economy) of a randomly chosen passenger on Delta Flight 833. e. Outside air temperature (Celsius) when Delta Flight 833 reaches 35,000 feet. f. Passenger rating (on 5-point Likert scale) of Delta's in-flight food choices.
a. Ratio b. Ratio c. Nominal d. Ordinal e. Interval f. Ordinal or Interval
Would you use a sample or census to measure each of the following? a. the number of workers currrently employed by Campbell Soup Company b. The average price of a can of Campbell's Cream of Mushroom Soup. c. The total earnings of workers employed by Campbell Soup Company last year.
a. census b. sample c. census
What type of data (categorical, discrete numerical, or continuous numerical) is each of the following variables? a. The miles on your car's odometer. b. The fat grams you ate for lunch yesterday. c. The name of the airline with the cheapest fare from New York to London. d. The brand of cell phone you own.
a. continuous numerical b. continuous numerical c. categorical d. categorical
Would you expect Starbucks to use a sample or census to measure each of the following? a. the percentage of repeat customers at a certain Starbucks on Saturday mornings. b. the number of chai tea latte orders last Saturday at a certain Starbucks. c. The average temperature of Starbucks coffee served on Saturday mornings. d. The revenue from coffee sales as a percentage of Starbucks' total revenue last year.
a. sample b. census c. sample d. census
Which type of data (cross-sectional or time series) is each variable? a. Value of Standard & Poor's 500 stock price index at the close of each trading day last year. b. Closing price of each of the 500 stocks in the S&P 500 index on the last trading day this week. c. Dividends per share paid by General Electric common stock for the last 20 quarters. d. Latest price/earnings ratios of 10 stocks in Bob's retirement portfolio.
a. time series b. cross-sectional c. time series d. cross-sectional
What kind of survey (mail, telephone, interview, Web, direct observation) would you recommend that a small laundry and dry cleaning business use for each of the following purposes? a. To estimate the proportion of customers preferring opening hours at 7 a.m. instead of 8 a.m. b. To estimate the proportion of customers who have only laundry and no dry cleaning. c. To estimate the proportion of residents in the same zip code who spend more than $20 a month on dry cleaning. d. To estimate the proportion of its seven employees who think it is too hot inside the building.
a. web or interview b. direct observation c. direct observation d. interview
Match the following words to their definitions: observation (obs), variable, data set
obs: single value variable: characteristic of interest data set: all values of all characteristics in a study
A binary variable (also called a dichotomous variable or dummy variable) has
only two possible values
What level of measurement (nominal, ordinal, interval, ratio) is appropriate for the movie rating system that you see in TV Guide ( )?
ordinal
_______________ data categorizes and ranks qualitative variables.
ordinal
A _______ includes all members of the group of interest.
population
"Bob didn't wear his lucky T-shirt to class, so he failed his chemistry exam." This best illustrates which fallacy
post hoc reasoning
In order to create a sample representative of the population, the analyst should use a ______ sampling technique.
random
A __________ survey will provide consistent responses from similar respondents over time.
reliable
When sampling from a population that has little variation (highly consistent), then the sample size needed would be________ than the sample needed from a population with large variation.
smaller, small, less, or fewer
Using a sample to make generalizations about an aspect of a population is called
statistical inference.
A population has groups that have a small amount of variation within them, but large variation among or between the groups themselves. The proper sampling technique is
stratified
A_______ sample is taken from homogeneous subgroups of the target population whereas a _______ sample is taken from different geographical regions within a target population.
stratified, cluster
Identify which of the sampling techniques listed are random.
stratified, cluster
An ethical data analyst would be least likely to
support management's desired conclusions.
The ________ population contains all the individuals in which one is interested
target
If the brand that had most sales was VW, then ______________.
the segment of the pie corresponding to VW would be the largest
Ergonomics is the science of making sure that human surroundings are adapted to human needs. How could statistics play a role in the following: Choosing the height of an office chair so that 95 percent of the employees (male and female) will feel it is the "right height" for their legs to reach the floor comfortably. Designing a drill press so its controls can be reached and its forces operated by an "average employee." Defining a doorway width so that a "typical" wheelchair can pass through without coming closer than 6 inches from either side. Setting the width of a parking space to accommodate 95 percent of all vehicles at your local Walmart. Choosing a font size so that a highway sign can be read in daylight at 100 meters by 95 percent of all drivers.
All of these involve taking samples from the population of interest and estimating the value of the variable of interest.
