ECO 4000 (pre-midterm 1)
A manager choses two people from a team of eight to give an oral presentation because she felt they were representative of the whole team's views. What sampling technique did she use in choosing these two people? Multiple Choice convenience simple random judgment cluster
Judgment
Which chart would be most appropriate to display PepsiCo's quarterly revenue for the most recent 20 quarters? Multiple Choice line chart Pareto chart scatter plot frequency polygon
Line chart
A valid survey is one that Multiple Choice measures what the researcher wants to measure. has been approved by top management. is administered by a professional statistician. has a large number of questions.
Measures what the researcher wants to measure
Which is not revealed on a scatter plot? Multiple Choice pairs of observed (xi, yi) data values nonlinear relationships between X and Y missing data values due to nonresponses unusual data values (outliers)
Missing data values due to nonresponses
A multi variable data set contains
More than two variables
Which is a time series variable? Multiple Choice VISA balances of 30 students on December 31 of this year net earnings reported by Xena Corporation for the last 10 quarters dollar exchange rates yesterday against 10 other world currencies titles of the top 10 movies in total revenue last week
Net earnings
Which is a time series variable?
Net earnings reported by Xena Corp for the last 10 quarters. (Last 10 quarters = time frame)
Your telephone area code is an example of a(n) __________ variable. Multiple Choice nominal ordinal interval ratio
Nominal
A problem with non random sampling is that
Not every item in the population has the same chance of being selected, as it should be
Scatter plots are Multiple Choice preferred in visualizing trends over time. able to reveal causal relationships. often fitted with a linear equation in Excel. applicable mainly to discrete data.
Often fitted with a linear equation in Excel
Your rating of the food served at a local restaurant using a three-point scale of 0 = gross, 1 = decent, 2 = yummy is __________ data. Multiple Choice nominal ordinal interval ratio
Ordinal
Which chart would be appropriate to compare staffed bed count in the three major hospitals in Las Vegas? Multiple Choice line chart Pareto chart pie chart histogram
Pie chart
Choosing actions that will result in the best outcome for the company and its customers is
Prescriptive analytics
Which statement is correct? Multiple Choice Selecting every fifth shopper arriving at a store will approximate a random sample of shoppers. Selecting only shoppers who drive SUVs is a stratified sampling method. A census is preferable to a sample for most business problems. Stratified samples are usually cheaper than other methods.
Selecting every fifth shopper arriving at a store will approximate a random sample of shoppers.
Measurements from a sample are called Multiple Choice statistics. inferences. parameters. variables.
Statistics
Which variable is least likely to be regarded as ratio data?
Student's evaluation of a professor's teaching
Which is not a practical constraint facing the business researcher or data analyst?
Survey respondents usually will tell the truth if well compensated.
"Smoking is not harmful. My Aunt Harriet smoked, but lived to age 90." This best illustrates which fallacy is not illustrated,
small sample generalization
"Tom's SUV rolled over. SUVs are dangerous." This best illustrates which fallacy?
small sample generalization
An ethical statistical consultant would not always
support management's desired conclusions.
"Circulation fell in the month after the new editor took over the newspaper Oxnard News Herald. The new editor should be fired." Which is not a serious fallacy in this conclusion?
using a biased sample
Because 25 percent of the students in my morning statistics class watch eight or more hours of television a week, I conclude that 25 percent of all students at the university watch eight or more hours of television a week. The most important logical weakness of this conclusion would be
using a sample that may not be representative of all students.
Which of the following statements is correct? Multiple Choice 1) A parameter is a measure that is calculated from a sample. 2) Statistics is the science of collecting, organizing, analyzing, interpreting, and presenting data. 3) For day-to-day business data analysis, most firms rely on a large staff of expert statisticians. 4) A statistical test result that is significant also has practical importance.
2) Statistics is the science of collecting, organizing, analyzing, interpreting, and presenting data.
Below is a sorted stem-and-leaf diagram for the measured speeds (miles per hour) of 49 randomly chosen vehicles on highway I-80 in Nebraska. What is the fourth slowest speed in the sorted data array? Stem unit = 10 Leaf unit = 1 Frequency Stem Leaf 1 4 9 1 5 5 17 6 0 1 2 2 2 4 5 5 5 5 6 6 8 8 9 9 9 19 7 0 1 1 1 2 3 3 3 4 5 6 6 6 7 7 8 9 9 9 7 8 0 1 3 3 5 5 7 4 9 0 1 2 2 49 Multiple Choice 61 60 55 It is impossible to tell.
61
Below is a sorted stem-and-leaf diagram for the measured speeds (miles per hour) of 49 randomly chosen vehicles on highway I-80 in Nebraska. Which is the modal class? Stem unit = 10 Leaf unit = 1 Frequency Stem Leaf 1 4 9 1 5 5 17 6 0 1 2 2 2 4 5 5 5 5 6 6 8 8 9 9 9 19 7 0 1 1 1 2 3 3 3 4 5 6 6 6 7 7 8 9 9 9 7 8 0 1 3 3 5 5 7 4 9 0 1 2 2 49 Multiple Choice 60 but less than 70. 70 but less than 80. 80 but less than 90. It is impossible to determine.
70 but less than 80
Below is a sorted stem-and-leaf diagram for the measured speeds (miles per hour) of 49 randomly chosen vehicles on highway I-80 in Nebraska. What is the highest observed speed? Stem unit = 10 Leaf unit = 1 Frequency Stem Leaf 1 4 9 1 5 5 17 6 0 1 2 2 2 4 5 5 5 5 6 6 8 8 9 9 9 19 7 0 1 1 1 2 3 3 3 4 5 6 6 6 7 7 8 9 9 9 7 8 0 1 3 3 5 5 7 4 9 0 1 2 2 49 Multiple Choice 92 90 87 It is impossible to tell.
92
A section of the population we have targeted for analysis is
A frame
Which of the following is a correct statement? Multiple Choice Choosing the third person listed on every fifth page of the phone book is stratified sampling. An advantage of a systematic sample is that no list of enumerated data items is required. Convenience sampling is used to study shoppers in convenience stores. Judgment sampling is an example of true random sampling.
An advantage of a systematic sample is that no list of enumerated data items is required.
Which of these deficiencies would be considered a major visual deception on a graph? Multiple Choice vague or unclear source using more than one color or font bar widths proportional to bar height using a dramatic graph title
Bar widths proportional to bar height
The width of a bin in a frequency distribution is known as the Multiple Choice midpoint. class limit. bin frequency. class interval.
Class interval
A marketing survey was sent to random samples of households in ten different neighborhoods near a new shopping mall. This is an example of Multiple Choice convenience sampling simple random sampling judgment sampling cluster sampling
Cluster sampling
From its 32 regions, the FAA selects six regions, and then randomly audits 25 departing commercial flights in each region for compliance with legal fuel and weight requirements. This is an example of Multiple Choice simple random sampling. stratified random sampling. cluster sampling. judgment sampling.
Cluster sampling
Professor Hardtack chose a sample of 7 students from his statistics class of 35 students by picking every student who was wearing red that day. Which kind of sample is this? Multiple Choice simple random sample judgment sample systematic sample convenience sample
Convenience sample
An advantage of convenience samples over random samples is that Multiple Choice they are easy to analyze. it is easier to determine the sample size needed. it is easier to calculate the sampling errors involved. data collection cost is reduced.
Data collection cost is reduced
A stratified sample is sometimes recommended when Multiple Choice the sample size is very large. the population is small compared to the sample. distinguishable strata can be identified in the populations. the population is spread out geographically.
Distinguishable strata can be identified in the populations
Which of the following statements is not true? Multiple Choice 1) A statistic is a single measure (usually numerical) that is calculated from a sample. 2) Statistics is the science of collecting, organizing, analyzing, interpreting, and presenting data. 3) For day-to-day business data analysis, most firms rely on a large staff of expert statisticians. 4) A statistical test may be significant yet have no practical importance.
For day-to-day business data analysis, most firms rely on a large staff of expert statisticians.
A section of the population we have targeted for analysis is Multiple Choice a statistic. a frame. a sample. a coven.
Frame
Because surveys are a measurement tool, they are often called Multiple Choice indicators. gizmos. instruments. devices.
Instruments
Temperature in degrees Fahrenheit is an example of a(n) __________ variable. Multiple Choice nominal ordinal interval ratio
Interval
Which type of data could be used to calculate an average? Multiple Choice nominal ordinal interval none of these responses
Interval
Quantitative variables use which two levels of measurement? Multiple Choice ordinal and ratio interval and ordinal nominal and ordinal interval and ratio
Interval and ratio
Which is most nearly correct regarding sampling error?
It cannot be eliminated by any statistical sampling method.
Thirty work orders are selected from a filing cabinet containing 500 work order folders by choosing every 15th folder. Which sampling method is this? Multiple Choice simple random sample systematic sample stratified sample cluster sample
Systematic
Which is a categorical variable? Multiple Choice the brand of jeans you usually wear the price you paid for your last pair of jeans the distance to the store where you purchased your last pair of jeans the number of pairs of jeans that you own
The brand of jeans you usually wear
Which is a discrete variable? Multiple Choice the time it takes to put on a pair of jeans the price you paid for your last pair of jeans the distance to the store where you purchased your last pair of jeans the number of pairs of jeans that you own
The number of pairs of jeans that you own
An advantage of convenience samples is that Multiple Choice the required sample size is easier to calculate. sampling error can be reduced. computation of statistics is easier. they are often quicker and cheaper.
They are often quicker and cheaper
Judgment sampling is sometimes preferred over random sampling, for example, when Multiple Choice the desired sample size is much larger than the population. the sampling budget is large and the population is conveniently located. time is short and the sampling budget is limited. the population is readily accessible and sampling is nondestructive.
Time is short and the sampling budget is limited
Sampling bias can best be reduced by
Utilizing random sampling
Which measurement exemplifies an interval scale but not a ratio scale? Multiple Choice weight (kilogram) of a randomly-chosen laptop computer in an office earnings per share of a randomly-chosen S&P 500 stock maximum wind speed (miles per hour) of a randomly-chosen tropical storm size (megabytes) of a randomly-chosen Excel spreadsheet water temperature (Fo) at Miami Beach on a randomly-chosen day
Water temperature (Fo) at Miami Beach on a randomly-chosen day
Which statement is correct? Multiple Choice Analysts rarely consult business periodicals (e.g., Bloomberg Businessweek). Web searches (e.g., Google) often yield unverifiable data. Government data sources (e.g., www.bls.gov) are often costly. Private statistical databases (e.g., CRSP) are usually free.
Web searches (e.g, Google) often yield unverifiable data
Which of the following is not a characteristic of an ideal statistician? Multiple Choice technically current (e.g., software) communicates well (both written and oral) always agrees with client's conclusions can deal with imperfect information
always agrees with client's conclusions
Which is not a reason for an average student to study statistics?
learn investment strategies
"Bob didn't wear his lucky T-shirt to class, so he failed his chemistry exam." This best illustrates which fallacy?
post hoc reasoning
Using data to develop models that forecast customer behavior would be
predictive analytics
An ethical data analyst would be least likely to
rely on consultants for all calculations.
A good data analyst
reports findings that may contradict client's ideas.