Stats week 1 HW
Determine whether the underlined value is a parameter or a statistic. The average score for a class of 28 students taking a calculus midterm exam was Modifying 72 % with underline . nothing
Parameter
Determine whether the data set is a population or a sample. Explain your reasoning. The number of garages for each house on a street.
Population, because it is a collection of the number of garages for all houses on the street.
Determine whether the data set is a population or a sample. Explain your reasoning. The heights of half of the students in a class
Sample, b/c it is a collection of heights for all of the students in the in a subset of all the students in the class.
Determine whether the data set is a population or a sample. Explain your reasoning. The number of children in four houses on a street of 15
Sample, because the collection of the number of children for four houses is a subset of all houses on the street.
How is a sample related to a population?
A sample is a subset of a population.
Name each level of measurement for which data can be qualitative. Select all the levels of measurement for which data can be qualitative.
Ordinal Nomina
Determine whether the variable is qualitative or quantitative. Explain your reasoning. Favorite brand of computer Is the variable qualitative or quantitative?
The variable id qualitative b/c a favorite brand an attribute or characteristic
Determine whether the variable is qualitative or quantitative. Explain your reasoning. Favorite musical style Is the variable qualitative or quantitative?
The variable is qualitative because a favorite musical style describes an attribute
Use the row of numbers shown below to generate 12 random numbers between 01 and 99. 14037 58527 10730 58053 35289 64701 29467 90923
14, 3, 75, 85, 27, 10, 73 , 5 , 80 , 53 , 35 , 2
The top five books on the best seller list last year are shown below. 1. The Forgotten 2. Threat Vector 3. Private London 4. Gone Girl 5. Kiss The Dead Identify the level of measurement of the data set. Explain your reasoning.
Ordinal. the data can be arranged in order, nut the differences between data entries are not meaningful.
Determine if the statement is true or false. If it is false, rewrite it as a true statement. It is impossible for the Census Bureau to obtain all the census data about the population of the United States.
The statement is true.
Use the row of numbers shown below to generate 12 random numbers between 01 and 99. 31046 68826 95853 40380 08397 02542 59339 88154 Starting at the beginning of the row, what are the first 12 numbers between 01 and 99 in the sample?
31 4 66 88 26 95 85 34 3 81 8 39
Suppose a survey of 584 women in the United States found that more than 68 % are the primary investor in their household. Which part of the survey represents the descriptive branch of statistics? Make an inference based on the results of the survey. Choose the best inference from the given information.
68 % of women in the sample are the primary investor in their household part 2 There is an association between U. S. women and being the primary investor their household.
Determine whether the statement is true or false. If it is false, rewrite it as a true statement. A population is the collection of some outcomes, responses, measurements, or counts that are of interest.
False. A population is the collection of all outcomes, responses, measurements, or counts that are of interest.
Determine whether the statement is true or false. If it is false, rewrite it as a true statement. Data at the ordinal level are quantitative only.
False. Data at the ordinal level can be qualitative or quantitative.
Determine whether the statement is true or false. If it is false, rewrite it as a true statement. Using a systematic sample guarantees that members of each group within a population will be sampled. Choose the correct answer below.
False. Using a stratified sample guarantees that members of each group within a population will be sampled.
A pharmaceutical company wants to test the effectiveness of a new allergy drug. The company identifies 250 females 30-35 years old who suffer from severe allergies. The subjects are randomly assigned into two groups. One group is given the new allergy drug and the other is given a placebo that looks exactly like the new allergy drug. After six months, the subjects' symptoms are studied and compared. Answer parts (a) through (c) below. a) Identify the experimental units and treatments used in this experiment. Choose the correct answer below. (b) Identify a potential problem with the experiment design being used and suggest a way to improve it. Choose the correct answer below. (c) How could this experiment be designed to be a double-blind? Choose the correct answer below.
The experimental units are the 30- to 35-year-old females being given the treatment. The treatment is the new allergy drug. There may be a bias on the part of the researcher if the researcher knows which patients were given the real drug. The study would be a double-blind study if both the researcher and the patient did not know which patient received the real drug or the placebo.
In a recent study, volunteers who had 8 hours of sleep were three times more likely to answer questions correctly on a math test than were sleep-deprived participants. Complete parts a through d. (a) Identify the sample used in the study. Choose the correct answer below. b) What is the sample's population? Choose the correct answer below (c) Which part of the study represents the descriptive branch of statistics? Choose the correct answer below. (d) Make an inference based on the results of the study. Choose the correct answer below.
The sample is the responses of the volunteers in the study the pop is collected of the response of all individuals who completed the math test the statement " 3 times more likely to answer the questions correctly ndividuals who are not sleep deprived will be more likely to answer math questions correctly than individuals who are sleep deprived.
In a recent study, volunteers who had 8 hours of sleep were three times more likely to answer questions correctly on a math test than were sleep-deprived participants. Complete parts a through d. (a) Identify the sample used in the study. Choose the correct answer below. (b) What is the sample's population? Choose the correct answer below. (c) Which part of the study represents the descriptive branch of statistics? Choose the correct answer below (d) Make an inference based on the results of the study. Choose the correct answer below.
The sample is the responses of the volunteers in the study the pop is the collection of the resp. of all individuals who completed the math test the statement " 3 times more likely to answer the questions correctly Individuals who are not sleep deprived will be more likely to answer math questions correctly than individuals who are sleep deprived
Determine whether the variable is qualitative or quantitative. Explain your reasoning. Eye color Is the variable qualitative or quantitative?
The variable is qualitative because color describes an attribute or characteristic.
Determine whether the variable is qualitative or quantitative. Explain your reasoning. Favorite rock group Is the variable qualitative or quantitative?
The variable is qualitative because a favorite rock group describes an attribute or characteristic.
Determine whether the variable is qualitative or quantitative. Explain your reasoning. Color of car driven Is the variable qualitative or quantitative?
The variable is qualitative because color describes an attribute or characteristic.
Determine whether the variable is qualitative or quantitative. Explain your reasoning. Amount of disk space in gigabytes Is the variable qualitative or quantitative?
The variable is quantitative because amount of disk space is found by measuring or counting.
Determine whether the data set is a population or a sample. Explain your reasoning. The height of each student in a classroom.
population, b/c it is a collection of heights for all students in the classroom.
The region of a country with the highest per capita income for the past six years is shown below. Northern Eastern Northeast Western Northern Southwest Determine whether the data are qualitative or quantitative and identify the data set's level of measurement. Are the data qualitative or quantitative? What is the data set's level of measurement?
qualitative nominal
The regions of a country with the six highest per capita incomes last year are shown below. 1. Northern 2. Southeast 3. Southwest 4. Southern 5. Eastern 6. Western Determine whether the data are qualitative or quantitative and identify the data set's level of measurement Are the data qualitative or quantitative? What is the data set's level of measurement?
qualitative ordinal
The masses left parenthesis in grams right parenthesis of a sample of a species of fish caught in the waters of a region are shown below. 23.6 23.3 22.4 22.3 24.6 24.1 24.5 20.3 20.6 Determine whether the data are qualitative or quantitative and identify the data set's level of measurement.
quantitative Ratio
Use the row of numbers shown below to generate 12 random numbers between 01 and 99. 65055 16884 33705 89888 50964 20237 36878 31122 Starting at the beginning of the row, what are the first 12 numbers between 01 and 99 in the sample?
06 05 51 68 84 33 70 58 98 88 50 96
A researcher wants to study the effects of sleep deprivation on motor skills. Nine people volunteer for the experiment: Amanda, Brian, Christine, David, Emily, Fred, George, Heather, and Ivan. Use the second row of digits in the random number table below to select a simple random sample of three subjects (ignore zeros). The other six subjects will go into the control group. If the subjects are numbered 1 through 9 alphabetically, what are the numbers of the three subjects selected? List the subjects that will go in the treatment group. Line/Column (1) (2) (3) (4) 1 12663 41156 64019 98021 2 16902 87195 56738 04609 3 63949 92781 15758 58246
1,6,9 The three subjects, in the order selected, are Amanda, Fred, and Ivan.
Determine if the survey question is biased. If the question is biased, suggest a better wording. How often do you eat fruit during an average month? Is the question biased? Choose the best question below.
No, because it does not lead the respondent to any particular answer The original question is not biased.
Identify the sampling techniques used, and discuss potential sources of bias (if any). Explain. In 1965, researchers used random digit dialing to call 1300 people and ask what obstacles kept them from attending town hall meetings What type of sampling was used?
Simple random sampling indiviuals many not be availbe the called only includes people wit phones ind. may have refused to participate
Determine whether you would take a census or use a sampling to collect data for the study described below. The average height of the 75 employees of a company. Would you take a census or use a sampling?
census
Use the Venn diagram to identify the population and the sample. A rectangular box reads, The income of home owners in a certain state, contains a smaller rectangular box that reads, The income of home owners in the state who work at home.
part 1 The income of home owners in the state part 2 The income of home owners in the state who
Use the Venn diagram to identify the population and the sample. A rectangular box reads, The party of registered voters in a certain country, contains a smaller rectangular box that reads, The party of registered voters in the country who voted in the last election. part 2 Choose the correct description of the sample
part 1 The party of registered voters in the country part 2 The party of registered voters in the country who voted in the last election
What is an inherent zero? Describe three examples of data sets that have inherent zeros and three that do not. Choose the correct answer below. Select three examples of data sets that have inherent zeros below.
An inherent zero is a zero that implies none. Average age of college students in years Average monthly precipitationin inches Max wind speed during a hurricane Temp in degrees Fahrenheit Average IQ of a HS class A student's level of happiness measured from 0 to 10 .
Use the Venn diagram to identify the population and the sample. A rectangular box reads, The income of home owners in a certain county, contains a smaller rectangular box that reads, The income of home owners in the county who have a garage.
part one the income of home owners in the country part 2 The income of home owners in the county who have a garage
The list of books that your friend read for school for the past five months is shown below. Kiss The Dead The Forgotten Threat Vector The Racketeer Spring Fever Identify the level of measurement of the data set. Explain your reasoning.
Nominal . The data are categorized using names comma labels comma or qualities comma but the data cannot
Determine whether the data set is a population or a sample. Explain your reasoning. The temperature in four state capitals out of 50
Sample, because the collection of temperatures for four state capitals is a subset of all state capitals.
Determine whether the statement is true or false. If it is false, rewrite it as a true statement. More types of calculations can be performed with data at the nominal level than with data at the interval level.
False. More types of calculations can be performed with data at the interval level than with data at the nominal level.
In a poll, 1 comma 004 women in a country were asked whether they favor or oppose the use of "federal tax dollars to fund medical research using stem cells obtained from human embryos." Among the respondents, 48% said that they were in favor. Describe the statistical study. Identify the sample for the given problem. Choose the correct answer below.
part 1 All women in the country part 2 The 1 ,004 women selected
Determine whether the data set is a population or a sample. Explain your reasoning. The number of radios in each household in a country.
Population, because it is a collection of the number of radios for all households in the country.
Determine whether the data set is a population or a sample. Explain your reasoning. The heights of half of the students in a class
Sample, because the collection of heights of half of the students is a subset of all students in the class.
Use the Venn diagram to identify the population and the sample. A rectangular box reads, The income of home owners in a certain state, contains a smaller rectangular box that reads, The income of home owners in the state who own a car. The income of home owners in a certain stateThe income of home ownersin the state whoown a car part 2 Choose the correct description of the sample.
part 1 The income of home owners in the state part 2 The income of the homeowners in the state who own a car.
Use the Venn diagram to identify the population and the sample. A rectangular box reads, The income of home owners in a certain country, contains a smaller rectangular box that reads, The income of home owners in the country who have a mortgage.
part1 The income of home owner in the country part2 The income of home owners in the country who have a mortgage
Determine whether the data set is a population or a sample. Explain your reasoning. The ages of one person per row in a cinema
Sample, b/c the collection of ages of one person per row is a subset of all people in the cinema.
Determine if the survey question is biased. If the question is biased, suggest a better wording. Why is eating eggs goodfor you? Is the question biased? Choose the best question below.
yes How do you think eating eggs affects your health?
Determine whether the data set is a population or a sample. Explain your reasoning. The number of floors in each home in a town.
Population, b/c it is collection of the number for all homes in the town.
Some polling agencies ask people to call a telephone number and give their response to a question. (a) List an advantage and a disadvantage of a survey conducted in this manner. (b) What sampling technique is used in such a survey? a) What is an advantage of this type of survey? Choose the correct answer below. What is a disadvantage of this type of survey? Choose the correct answer below. Convenience sampling
This usually results in a savings in the survey cost There tends to be a lower response rate and this may introduce a bias into the sample. Only a certain segment of the population might respond. Convenience sampling
What is the difference between a random sample and a simple random sample?
With a random sample, each individual has the same chance of being selected. With a simple random sample, all samples of the same size have the same chance of being selected
Determine whether the statement is true or false. If it is false, rewrite it as a true statement. A statistic is a measure that describes a population characteristic
False. A statistic is the science of collecting, organizing, analyzing, and interpreting data in order to make decisions.
The graph to the right shows the responses to the question comma "Does global warming contribute to El Nino question mark " Identify the level of measurement of the data listed on the horizontal and vertical axes in the figure.
Identify the level of measurement of the data listed on the horizontal axis in the figure. Choose the correct answer below. Interval 1st Ordinal 2nd question Your answer is correct. dentify the level of measurement of the data listed on the vertical axis in the figure. Choose the correct answer below. Ratio first and 2nd Your answer is correct.
Observational studies are sometimes referred to as natural experiments. Explain what this means. Choose the correct answer below.
In an observational study, a researcher measures characteristics of interest of a part of a population but does not change existing conditions
Determine whether the data set is a population or a sample. Explain your reasoning. The salary of each baseball player in a league.
Population, because it id a collection of salaries for all baseball in the league.
The regions of a country with the six highest per capita incomes last year are shown below. 1. Southern 2. Northern 3. Eastern 4. Western 5. Southwest 6. Southeast Determine whether the data are qualitative or quantitative and identify the data set's level of measurement. Are the data qualitative or quantitative? What is the data set's level of measurement?
Qualitative Ordinal
The list of books that your friend read for school for the past five months is shown below. Spring Fever Private London The Racketeer The Forgotten Threat Vector Identify the level of measurement of the data set. Explain your reasoning. What is the data set's level of measurement? Explain your reasoni
Nominal The data are categorized using names comma labels comma or qualities comma but the data cannot be ranked or arranged in order
The list of books that your friend read for school for the past five months is shown below. Gone Girl Kiss The Dead Spring Fever Threat Vector The Forgotten Identify the level of measurement of the data set. Explain your reasoning.
Norminal. The data are categorized using names, labels, or qualities, but the data cannot be ranked or arranged in order.
The following appear on a physician's intake form. Identify the level of measurement of the data. Change in health left parenthesis scale of minus 5 to 5 right parenthesis left parenthesis b right parenthesis Weight left parenthesis c right parenthesis Allergies left parenthesis d right parenthesis nbsp Year of birth (a) What is the level of measurement for "Change in health left parenthesis scale of minus 5 to 5 right parenthesis "? (b) What is the level of measurement for "Weight "? (c) What is the level of measurement for "Allergies "? (d) What is the level of measurement for "Year of birth "?
Ordinal Ratio Normial interval
The lengths left parenthesis in inches right parenthesis of a sample of a species of fish caught in the waters of a region are shown below. 17.7 17.2 17.1 17.1 17.8 19.7 21.6 19.9 21.8 Determine whether the data are qualitative or quantitative and identify the data set's level of measurement.
Quantitative Ratio
Determine whether the data set is a population or a sample. Explain your reasoning. The ages of three families of people in an apartment building housing ten families
Sample, b/c the collection of ages for three families of people is a subset of all people living in the building.
Determine whether the data set is a population or a sample. Explain your reasoning. The grades of 5 students in a classroom of 30
Sample, because the collection of 5 students' grades is a subset of all students in the class.
Determine whether the data set is a population or a sample. Explain your reasoning. The ages of one person per row in a cinema
Sample, because the collection of ages of one person per row is a subset of all people in the cinema.
Identify the sampling techniques used, and discuss potential sources of bias (if any). Explain. Chosen at random, 490 customers at a department store are contacted and asked their opinions of the service they received. What type of sampling is used? What potential sources of bias are present, if any? Select all that apply.
Simple random sampling is used, since the business is selecting from its customers at random, and all samples of 490customers have an equal chance of being selected. The wording of the question asked to the customers may influence them towards a particular response. The results would not be usable in this case.
Determine whether the given value is a statistic or a parameter. Upper A sample of professors is selected and it is found that 25 % own a television.
Statistic because the value is a numerical measurement describing a characteristic of a sample
The regions with the six highest volumes of sales for a corporation last year are shown below. 1. Eastern 2. Northwest 3. Southeast 4. Southern 5. Northeast 6. Western Determine whether the data are qualitative or quantitative and identify the data set's level of measurement Are the data qualitative or quantitative? What is the data set's level of measurement?
Qualitative Ordinal
Identify the sampling techniques used, and discuss potential sources of bias (if any). Explain. In 1965, researchers used random digit dialing to call 1300 people and ask what obstacles kept them from eating healthier . What type of sampling was used? What potential sources of bias were present, if any? Select all that apply.
Simple random sampling was used, since each number had an equal chance of being dialed, so all samples of 1300 phone numbers had an equal chance of being selected indiviuals many not be availbe the called only includes people wit phones ind. may have refused to participate
Identify the sampling techniques used, and discuss potential sources of bias (if any). Explain. Corn is planted on a 54 -acre field. The field is divided into one-acre subplots. A sample is taken from each subplot to estimate the harvest. What potential sources of bias are present, if any? Select all that apply
Stratified sampling is used, since the field is divided into subplots and a random sample is taken from each subplot. Certain subplots may have more or fewer corn plants than others. Samples from these subplots may bias the overall sample
Determine whether the variable is qualitative or quantitative. Explain your reasoning. Amount of money spent on CDs this year Is the variable qualitative or quantitative?
The variable is quantitative because amount of money is found by measuring or counting.
A company has been rating television programs for more than 60 years. It uses several sampling procedures, but its main one is to track the viewing patterns of 20,000 households. These contain more than 45,000 people and are chosen to form a cross section of the overall population. The households represent various locations, ethnic groups, and income brackets. The data gathered from the sample of 20,000 households are used to draw inferences about the population of all households in the United States. Complete parts (a) and (b) below. What strata are used in the sample? Choose the correct answer below. Why is it important to have a stratified sample for these ratings? Choose the correct answer below.
The various locations, ethnic groups, and income brackets that are represented Stratified sampling ensures that each segment of the population is represented