Applied Stat - Textbook Questions
Specify if the random variable is discrete or continuous. W = weight of a watermelon a. discrete b. continuous
b. continuous
True or False: A bar chart excels at showing precise values.
False
True or False: A confidence interval always gives a correct estimate of the population parameter.
False
True or False: A data label is a category name.
False
True or False: A horizontal bar chat may be preferable for conveying the number of floors for the world's 5 tallest buildings.
False
True or False: A person observes cars that drive past. Y is assigned the car's manufacturer, which may be Ford, Chevy, Toyota, or Honda. Y is a random variable.
False
True or False: A radar gun records a car's speed. A sign displays the text SPEEDING or NOT SPEEDING. The text displayed is a random variable.
False
True or False: A research defines an experiment to be flipping two coins. Frank flips two coins and observes the outcome HT. The sample space is {H,T}.
False
True or False: Charts are useful for small datasets, but become too crowded when used with large datasets.
False
True or False: Each point in a scatter plot lies somewhere on the regression curve.
False
True or False: Lower p-values imply greater practical significance of the result of a hypothesis test.
False
True or False: Sally conducts the experiment of rolling a die, repeating the experiment three times, resulting in the three outcomes 2, 4, and 5. The 2, 4, and 5 represent the sample space.
False
True or False: The more gridlines drawn in a bar chart, the better.
False
True or False: The p-value is the same as the significance level α.
False
True or False: The true population parameter is p=.5. An estimator that produces a confidence interval of [.42,.49] is accurate.
False
A house's color. a. quantitative b. categorical
b. categorical
True or False: A bar chart excels at showing relative values.
True
True or False: A confidence interval estimate of a population parameter is constructed around the sample statistic.
True
True or False: A horizontal bar chart may be preferable if many categories exist.
True
True or False: A horizontal bar chart may be preferable if the category labels are long.
True
True or False: A horizontal bar chart may be preferable to depict different companies' annual profits, some of which are negative.
True
True or False: A person wins $100 per dot on the roll of a die. Z is the amount won on a die roll. Z is a random variable.
True
True or False: A poll has a margin of error of ±2.5%. The width of the corresponding confidence interval is 5%.
True
True or False: A research defines an experiment to be flipping two coins. Frank flips two coins and observes heads on the first coin and tails on the second coin, represented as HT. HT is an outcome of this experiment.
True
True or False: A survey asks a participant to indicate age. Y is assigned the value of the response. Which ranges from 1 to 120. Y is a random variable.
True
True or False: A survey asks a participant to indicate eye color. Possible responses are blue, brown, or green. Y is assigned 1 for blue, 2 for brown, and 3 for green. Y is a random variable.
True
True or False: Charts can be used to identify relationships between different variables.
True
True or False: Jittering gives a more accurate sense of a dataset's features.
True
True or False: Sally rolls a 6-sided die. The sample space is {1, 2, 3, 4, 5, 6}.
True
True or False: Some airports, like John Wayne Airport in California, measure noise levels when a plane flies over houses near the airport and fines airlines that exceed thresholds. Y is assigned 1 if a plane's measured sound exceeds 100 dB, and 0 otherwise. Y is a random variable.
True
True or False: The same p-value can imply statistical significance in some hypothesis tests but not others.
True
Specify if the random variable is discrete or continuous. B = the alcohol concentration in a person's blood a. discrete b. continuous
b. continuous
Specify if the random variable is discrete or continuous. D = distance a ball is thrown a. discrete b. continuous
b. continuous
Noah conducts an experiment by flipping a coin twice. The sample space for this experiment is {HH, HT, TH, TT}. Which of the following is a simple event? a. Noah flips two heads. b. Noah flips one heads and one tails. c. Since Noah is flipping the coin twice, no simple events can exist.
a. Noah flips two heads
Null hypothesis: The suspect did not commit a crime. Actual outcome: The suspect did not commit the crime. Decision: The suspect was found guilty. a. Type I error b. Type II error c. No error
a. Type I error
Joe rolls a 6-sided die and records the number of dots displayed. The roll of the die is _____. a. an experiment b. an outcome
a. an experiment
The x-axis is the year ranging from 2000 to 2015, the y-axis is the amount of rainfall. a. appropriate b. not appropriate
a. appropriate
The x-axis shows a movie rating: G, PG, PG-13, and NC-17. The y-axis is the number of movies released in 2015 of a given rating. a. appropriate b. not appropriate
a. appropriate
A major polling company in the United States randomly selects Alaska, Illinois, Texas, Florida, and Pennsylvania as the states from which to select households for a survey. a. cluster sampling b. systematic sampling c. simple random sampling d. stratified sampling
a. cluster sampling
Gallons in a car's gas tank. a. continuous b. discrete
a. continuous
Height of a human. a. continuous b. discrete
a. continuous
Width of a house. a. continuous b. discrete
a. continuous
Specify if the random variable is discrete or continuous. X = 1 if a person passes a driver's test and X = 0 if the person fails a. discrete b. continuous
a. discrete
Specify if the random variable is discrete or continuous. X = number of red cars in a parking lot a. discrete b. continuous
a. discrete
Specify if the random variable is discrete or continuous. Z = fraction of games a team wins in a 16- game football season a. discrete b. continuous
a. discrete
A student is given a test worth 100 points. a. experiment b. outcome (and also an event) c. sample space d. event
a. experiment
Given data where the x-value represents the area to be painted in square feet and the y-value represents amount of paint in gallons, the regression curve is likely _____. a. linear b. non-linear
a. linear
A measure of the center of a distribution a. mean b. variance c. standard deviation
a. mean
A car comes in 5 possible colors: red, grey, brown, black, and white. a. nominal b. ordinal
a. nominal
A form asks a person to indicate a country of birth. a. nominal b. ordinal
a. nominal
An Amazon product has 5 possible ratings: 1 star, 2 stars, 3 stars, 4 stars, or 5 stars. a. nominal b. ordinal
a. nominal
An analysis obtains the salaries of all 167 federal appeals court judges in 2014 and computes the mean salary to be $211,200. Is $211,200 a parameter or a statistic? a. parameter b. statistic
a. parameter
An analyst is asked to determine how many miles each employee commutes at a 20-person company. Should the analyst collect data from the population or from a sample? a. population b. sample
a. population
An analyst obtains the salaries of all 167 federal appeals court judges in 2014 and computes the mean salary to be $211,200. Are the 167 judges a population or a sample? a. population b. sample
a. population
"Numerical variable" is likely another term for which type? a. quantitative b. categorical
a. quantitative
A car's age. a. quantitative b. categorical
a. quantitative
A house's square footage. a. quantitative b. categorical
a. quantitative
A survey asking how often respondents send text messages while driving routinely underestimates the actual frequency of texting while driving. a. social desirability bias b. extreme responding c. undercoverage d. nonresponse bias e. acquiescence bias
a. social desirability bias
The amount of data collected worldwide in 2016 is about _____ zettabytes. a. 1 b. 10 c. 100
b. 10
Null hypothesis: The suspect did not commit a crime. Actual outcome: The suspect committed the crime. Decision: the suspect was not found guilty. a. Type I error b. Type II error c. No error
b. Type II error
The event B is rolling less than a 3 on a six-sided die. B is best described as a _____. a. a simple event b. a compound event c. not an event
b. a compound event
Joe rolls a 6-sided die and records the number of dots facing up. 4 Dots are facing up. The 4 dots facing up are _____. a. an experiment b. an outcome
b. an outcome
"Nominal variable" is likely another term for which time? (Nominal refers to "name"). a. quantitative b. categorical
b. categorical
"Qualitative variable" is likely another term for which type? a. quantitative b. categorical
b. categorical
A car's maker. a. quantitative b. categorical
b. categorical
A house's address. a. quantitative b. categorical
b. categorical
Specify if the random variable is discrete or continuous. Y = the water temperature at different ocean depths a. discrete b. continuous
b. continuous
Parents and doctors with to compare a child's heigh to other children's heights of the same age. The height is the _____ variable. a. dependent b. independent
b. dependent
Air molecules in a house. a. continuous b. discrete
b. discrete
Fingers on a human's hands. a. continuous b. discrete
b. discrete
Hairs on a human's head. a. continuous b. discrete
b. discrete
The majority of reviews on a restaurant's social media site are either one-star or five-star reviews. a. social desirability bias b. extreme responding c. undercoverage d. nonresponse bias e. acquiescence bias
b. extreme responding
A dean wishes to know whether increasing faculty may lead to better rank. The number of faculty is the ______ variable. a. dependent b. independent
b. independent
A news station records temperature and humidity for various days and then creates a scatter plot to determine if any relationship exists. Is either temperature or humidity an obvious independent variable? a. yes b. no
b. no
Given data where the x-value represents a person's height and the y-value represents a person's age for ages 1-50, the regression curve is likely _____. a. linear b. non-linear
b. non-linear
The x-axis is a color: black, blue, green, red, silver, or white. The y-axis is the number of cars of a given color. a. appropriate b. not appropriate
b. not appropriate
A movie has 5 possible ratings: G, PG, PG-13, R, and NC-17. a. nominal b. ordinal
b. ordinal
The student's score on the exam, such as 95. a. experiment b. outcome (and also an event) c. sample space d. event
b. outcome (and also an event)
A car maker's cars have a miles-per-gallon rating that can range from 10 to 60. a. categorical b. quantitative
b. quantitative
An analyst is asked to determine how many miles each employee commutes at Microsoft, which has over 100,000 employees. Should the analyst collect data from the population or on a sample? a. population b. sample
b. sample
An analyst surveys 1,000 registered nurses across the U.S. and computes their mean earnings to be $27/hr. The analyst reports that U.S. nurses have mean earnings of $27/hr. Are the 1,000 nurses a population or a sample? a. population b. sample
b. sample
An analyst surveys 1,000 registered nurses across the U.S. and computes their mean earnings to be $27/hr. The analyst reports that U.S. nurses have mean earnings of $27/hr. Is $27/hr a parameter or a statistic? a. parameter b. statistic
b. statistic
To select households for the survey, the company consults the property tax rolls in a specific area, and selects every household with an odd street number for the survey. a. cluster sampling b. systematic sampling c. simple random sampling d. stratified sampling
b. systematic sampling
Measure involving the squared differences of X from E(X) a. mean b. variance c. standard deviation
b. variance
Null hypothesis: The suspect did not commit a crime. Actual outcome: The suspect committed the crime. Decision: The suspect was found guilty. a. Type I error b. Type II error c. No error
c. No error
A gym teacher defines an experiment to be running a mile race three times in gym class. Sue runs the mile three times. Sue's fastest time was 6:10. This time can best be described as _____. a. a simple event b. a compound event c. not an event
c. not an event
A zettabyte is _____ bytes. a. one trillion b. 1,000 trillion c. one sextillion
c. one sextillion
The range of possible scores on the test, [0, 100]. a. experiment b. outcome (and also an event) c. sample space d. event
c. sample space
To select households for the survey, the company consults the property tax rolls in a specific area, and selects households at random for the survey. a. cluster sampling b. systematic sampling c. simple random sampling d. stratified sampling
c. simple random sampling
A measure of spread with units the same as the random variable a. mean b. variance c. standard deviation
c. standard deviation
Students conducting a survey on a campus-wide issue only conducted the survey in front of the main engineering building, and the concerns of humanities students on the other side of the campus were not adequately addressed. a. social desirability bias b. extreme responding c. undercoverage d. nonresponse bias e. acquiescence bias
c. undercoverage
Achieving a passing score on the test. a. experiment b. outcome (and also an event) c. sample space d. event
d. event
Which was a substantial source of computerized data before the year 1990? a. social network data b. internet search data c. medical records d. none of the above
d. none of the above
An internet survey sent to a remote rural area with poor internet penetration had only a 3% response rate. a. social desirability bias b. extreme responding c. undercoverage d. nonresponse bias e. acquiescence bias
d. nonresponse bias
To select households for the survey, the company consults the property tax rolls in a specific area, and subdivides households into several property value brackets. Households are then randomly and proportionally selected from each bracket. a. cluster sampling b. systematic sampling c. simple random sampling d. stratified sampling
d. stratified sampling
A question on a political ballot contains the question "Is Freedom Important?," which is a relatively non-controversial statement with which 98% of voters agreed. a. social desirability bias b. extreme responding c. undercoverage d. nonresponse bias e. acquiescence bias
e. acquiescence bias