Research Methods Part 1 Ch. 1
What is the complete collection of all individuals (scores, people, measurements, and so on) to be studied; the collection is complete in the sense that it includes all of the individuals to be studied
Population
In what types of studies are data collected in the future from groups sharing common factors (called cohorts)
Prospective (or longitudinal or cohort) study
What type of data consists of names or labels (representing categories) Example: The genders (male/female) of professional athletes Example: Shirt numbers on professional athletes uniforms - substitutes for names.
Qualitative (or categorical or attribute) data
1.2.9 Identify whether the given value is a statistic or a parameter. In a study of all of the babies born at five different hospitals in Kentucky, it was found that the average (mean) weight at birth of those babies born at those hospitals was 3186.2 grams. The given value is a __________ because the numerical measurement describes a characteristic of a __________.
- parameter - population
1.2.9 Identify whether the given value is a statistic or a parameter. In a study of 500 of the babies born at five different hospitals in Massachusetts, it was found that the average (mean) weight at birth of those babies born at those hospitals was 3206.6 grams. The given value is a __________ because the numerical measurement describes a characteristic of a __________.
- statistic - sample
Match each level of measurement to its definition 1. categories only 2. categories with some order 3. differences but no natural starting point 4. differences and a natural starting point
1. Nominal 2. Ordinal 3. Interval 4. Ratio
what are the 6 Methods of Sampling
1. Random 2. Systematic 3. Convenience 4. Stratified 5. Cluster 6. Multistage
What level of measurement involves data that can be arranged in some order, but differences between data values either cannot be determined or are meaningless Example: Course grades A, B, C, D, or F
Ordinal level of measurement
Statistic vs Parameter What is a numerical measurement describing some characteristic of a POPULATION.
Parameter
Aside from continuous data and discrete data, what is Another way to classify data?
to use levels of measurement.
Census vs Sample What is a collection of data from every member of a population called?
census
1.3.15 For the following scenario, identify which of these types of sampling is used: random, systematic, convenience, stratified, or cluster. A researcher collects sample data by randomly selecting 25 hospital employees from each of the age categories of under 30, 30 to 50, and over 50. Choose the correct answer below. A. Cluster B. Systematic C. Convenience D. Random E. Stratified
E. Stratified
Statistic vs Parameter What is a numerical measurement describing some characteristic of a SAMPLE.
Statistic
Census vs Sample What is a sub-collection of members selected from a population called?
Sample
What type of data result from infinitely many possible values that correspond to some continuous scale that covers a range of values without gaps, interruptions, or jumps? Example: The amount of milk that a cow produces; e.g. 2.343115 gallons per day
- Continuous (numerical) data
What type of data result when the number of possible values is either a finite number or a 'countable' number (i.e. the number of possible values is 0, 1, 2, 3, . . .) Example: The number of eggs that a hen lays
- Discrete data
What term is used to describe the repetition of an experiment on more than one subject. Samples should be large enough so that the erratic behavior that is characteristic of very small samples will not disguise the true effects of different treatments.
Replication
1.3.15 For the following scenario, identify which of these types of sampling is used: random, systematic, convenience, stratified, or cluster. A researcher collects sample data by dividing a floorplan of the hospital into sections and choosing all employees in three of them Choose the correct answer below. A. Cluster B. Systematic C. Convenience D. Random E. Stratified
A. Cluster
1.1.11 Determine whether the sampling method described below appears to be sound or is flawed. In a recent year, a health survey, conductedconducted by a reputable medical schoola reputable medical school, selected more than 70007000 subjectssubjects who were given physical examsphysical exams. Subjects were selectedwere selected through a somewhatthrough a somewhat complicated procedurecomplicated procedure designed todesigned to obtain results that areobtain results that are representative of the population.representative of the population. Choose the correct answer below. A. It appears to be sound because the sample is random with no obvious potential for bias.It appears to be sound because the sample is random with no obvious potential for bias. B. It is flawed because the source of the data is biased and has an incentive to produce certain results. C. It is flawed because the sample does not include the entire population in question. D. It is flawed because it is a voluntary response sample.It is flawed because it is a voluntary response sample.
A. It appears to be sound because the sample is random with no obvious potential for bias.It appears to be sound because the sample is random with no obvious potential for bias.
1.1.25 Several studies showed that after eating chocolateafter eating chocolate, subjects had increased blood levelsincreased blood levels of antioxidants. Antioxidants have been associated withof antioxidants. Antioxidants have been associated with decreased risk of heart disease.decreased risk of heart disease. A candy companycandy company financed this research. Identify what is wrong. Choose the correct answer below. A. It is questionable that the sponsor is a candy company because this sponsor can be greatly affected by the conclusion. B. It is not possible to take accurate measurements. C. Since the research is composed of voluntary response samples, there may be key data points missing. D. The data used in the studies is not reliable because it was not measured by the administrator.
A. It is questionable that the sponsor is a candy company because this sponsor can be greatly affected by the conclusion.
what type of sampling involves the subdivision of the population into at least two different subgroups that share the same characteristics, then draw a sample from each subgroup (or stratum)
Stratified Sampling
1.3.13 Identify which type of sampling is used: random, systematic, convenience, stratified, or cluster. To determine customer opinion of their check-in service, American Airlines randomly selects 120 flights during a certain week and surveys all passengers on the flights. Which type of sampling is used? A. Cluster B. Convenience C. Random D. Stratified E. Systematic
A. Cluster
1.1.RA-1 Which of the following is typically the least important factor to consider when conducting a statistical analysis of data? Choose the correct answer below A. formula calculation B. context of the data C. sampling method D. source of the data
A. formula calculation
1.1.RA-8 Survey questions may be misleading if they are "loaded." To what does "loaded" refer? Choose the correct answer below A. not concise; very long drawn out questions B. intentionally worded to elicit a desired response C. too much data D. questions that trigger a nonresponse
B. intentionally worded to elicit a desired response
1.2.33 Determine whether the given value is from a discrete or continuous data set. When a car is randomly selected, it is found to have 4 windows Choose the correct answer below. A. A discrete data set because there are infinitely many possible values and those values can be counted. B. A discrete data set because there are a finite number of possible values. C. A continuous data set because there are infinitely many possible values and those values cannot be counted. D. The data set is neither continuous nor discrete.
B. A discrete data set because there are a finite number of possible values.
What are test subjects involved in an experiment called?
Experimental Units
Does correlation imply causality?
- NO - Concluding that one variable causes the other variable when in fact the variables are linked - Two variables may seemed linked, smoking and pulse rate, this relationship is called correlation. Cannot conclude the one causes the other.
What two methods of research study are there?
- Observational study - Experimental Study
What type of error involves the difference between a sample result and the true population result; such an error results from chance sample fluctuations
- Sampling error
1.2.13 Determine whether the data are from a discrete or continuous data set. In a study of weight gains by college students in their freshman year, researchers record the numbers of visits home by randomly selected students. Since the numbers of visits home __________ countable, the data are from a __________ data set.
- are - discrete
1.2.17 Determine whether the data are from a discrete or continuous data set. A sample of married couples is randomly selected and the number of children in each family is recorded. Since the numbers of children __________ countable, the data are from a __________ data set.
- are - discrete
1.2.13 Determine whether the data are from a discrete or continuous data set. In a study of weight gains by college students in their freshman year, researchers record the amounts of weight gained by randomly selected students Since the amounts of weight gained __________ countable, the data are from a __________ data set.
- are not - continuous
1.2.17 Determine whether the data are from a discrete or continuous data set. A sample of married couples is randomly selected and the difference in heights for each couple is recorded. Since the differences in heights __________ countable, the data are from a __________ data set.
- are not - continuous
Quantitative data can further be described by distinguishing between __________ and __________ types.
- discrete - continuous
1.1.15 Determine whether the results appear to have statistical significance, and also determine whether the results appear to have practical significance. In a study of a gender selection method used to increase the likelihood of a baby being born a girl, 2078 users of the method gave birth to 1022 boys and 1056 girls. There is about aa 23% chance of getting that many girls if the method had no effect. Because there is a 23% chance of getting that many girls by chance, the method __________________. __________ couples would likely use a procedure that raises the likelihood of a girl from the approximately 50% rate expected by chance to the ______% produced by this method, so this method _____________.
- does not have statistical significance - Not many - 51% - does not have practical significance
1.2.11 Determine whether the given value is a statistic or a parameter. In a study of all 4767 seniors at a college, it is found that 65% own a computer. Choose the correct statement below. A. Parameter because the value is a numerical measurement describing a characteristic of a population. B. Parameter because the value is a numerical measurement describing a characteristic of a sample. C. Statistic because the value is a numerical measurement describing a characteristic of a sample. D. Statistic because the value is a numerical measurement describing a characteristic of a population.
A. Parameter because the value is a numerical measurement describing a characteristic of a population.
1.2.23 For the given description of data, determine which of the four levels of measurement (nominal, ordinal, interval, ratio) is most appropriate. Year of birth of subject Choose the correct answer below. A. The interval level of measurement is most appropriate because the data can be ordered , differences (obtained by subtraction) can be found and are meaningful, but there is no natural zero starting point. B. The ratio level of measurement is most appropriate because the data can be ordered, differences differences (obtained by subtraction) can be found and are meaningful , and there is a natural zero starting point C. The nominal level of measurement is most appropriate because the data cannot be ordered. D. The ordinal level of measurement is most appropriate because the data can be ordered , but differences (obtained by subtraction) cannot be found or are meaningless
A. The interval level of measurement is most appropriate because the data can be ordered , differences (obtained by subtraction) can be found and are meaningful, but there is no natural zero starting point.
1.1.17 Refer to the table of body temperatures (degrees Fahrenheit). Is there some meaningful way in which each body temperature recorded at 8 AM is matched with the 12 AM temperature? A. Yes. Each column of 8 AM and 12 AM temperatures is recorded from the same subject, so each pair is matched. B. Yes. The 8 AM temperatures are all from one individual over five days and the 12 AM temperatures are from a different individual on the same five days, so each pair is matched. C. No. The 8 AM temperatures are from one individual over five days and the 12 AM temperatures are from another individual over five days. D. Yes. The 8 AM temperatures are all from one individual over five days and the 12 AM temperatures are from the same individual on the same five days, so each pair is matched.
A. Yes. Each column of 8 AM and 12 AM temperatures is recorded from the same subject, so each pair is matched.
USA today Posted this question on the electronic version of its newspaper." Should guys pay for the first date?". Of the 1148 subjects he decided to respond 85% of them said yes. A. what is wrong with this survey? B. is the value of 85% a statistic or a parameter? C. does the survey constitute an experiment or an observational study
A. samples like this, posted on an electronic newspaper, is a voluntary response sample, therefore the results are questionable B. Since the 85% represents the percent the sample who said yes, it is a statistic. C. because we are only observing, and not attempting to modify the individuals research methods exam you what's the difference in the just twisted in the study, it is an observational Study
1.1.RA-6 What is the goal of learning statistics? Choose the correct answer below A. to learn to distinguish between the statistical conclusions that are likely to be valid and those that are seriously flawed B. to accept the source of the data blindly C. to use statistics for deception D. to use voluntary response samples to imply results about the population
A. to learn to distinguish between the statistical conclusions that are likely to be valid and those that are seriously flawed
1.1.29 In a survey of 3326 randomly selected U.S. adults, 49% reported that they have at least one chronic health condition, such as diabetes or high blood pressure. Complete parts (a) through (d) below. Part A: What is 49% of 3326 adults? ___________ adults (Type an integer or a decimal. Do not round.) Part B: Could the result from part (a) be the actual number of survey subjects who have at least one chronic condition? a. No, the result from part (a) could not be the actual number of survey subjects because that result is too high. b. No, the result from part (a) could not be the actual number of survey subjects because a count of people must result in a whole number. c. Yes, the result from part (a) could be the actual number of survey subjects because the results are statistically significant. d. Yes, the result from part (a) could be the actual number of survey subjects because the survey numbers are accurate. C. What is the actual number of survey subjects who have at least one chronic condition? A possible value for the actual number of survey subjects is __________ adults. Part D: . Among those surveyed, 1183 were called by landline and 2143 were called by cell phone. What percentage of the survey subjects were called by landline __________%
A.) 1629.74 adults B.) b. No, the result from part (a) could not be the actual number of survey subjects because a count of people must result in a whole number. C.) 1630 adults D.) 35.6%
1.) currently, there are 4612 colleges in the United States, and the number of full Time student is 13,203, 477 A.) are the numbers of hospitals in different states discrete or continuous? B.) what is the level of measurement for the numbers of hospitals in different years? (nominal, ordinal, interval, or ratio) C.) what is wrong with surveying college students by mailing questionnaires to 10,000 of them who are randomly selected? D.) if we randomly College students in each of the 50 states, what type of sample is obtained? (random, systematic, convenience, stratified, cluster) E.) if we randomly select 4 colleges and survey all of their full-time students, what type of sample is obtained? (random, systematic, convenience, stratified, cluster)
A.) discrete B.) ratio - since the number of full-time college students can be arranged in order, differences can be found and are meaningful, and if there is a natural zero starting point that represents zero Full time students. C.) e-mail responses would be a voluntary response sample, so those with strong opinions or greater interest in the topics are more likely to respond. It is very possible that the results do not reflect the true opinions of the population of all full-time College students. D.) because we have divided the country into 50 groups, and randomly selected 50 students from each of those groups, the sample is STRATIFIED E.) cluster sample: the population area has been divided into clusters, colleges, then 4 of these colleges have been randomly selected and all of the students were surveyed.
1.2.33 Determine whether the given value is from a discrete or continuous data set. When a car is randomly selected, it is found to have enough room to seat 2 people Choose the correct answer below. A. A discrete data set because there are infinitely many possible values and those values can be counted. B. A discrete data set because there are a finite number of possible values. C. A continuous data set because there are infinitely many possible values and those values cannot be counted. D. The data set is neither continuous nor discrete.
B. A discrete data set because there are a finite number of possible values.
1.1.32 A researcher was once criticized for falsifying data. Among his data were figures obtained from 6 groups of mice, with 20 individual mice in each group. These values were given for the percentage of successes in each group: 53%, 58%, 63%, 46%, 48%, 67%. What's wrong with those values? Choose the correct answer below. A. All percentages of success should be multiples of 40. The given percentages cannot be correct. B. All percentages of success should be multiples of 5. The given percentages cannot be correct. C. All percentages of success should be multiples of 6. The given percentages cannot be correct. D. All percentages of success should be multiples of 20. The given percentages cannot be correct.
B. All percentages of success should be multiples of 5. The given percentages cannot be correct.
1.1.22 Refer to the accompanying data table on back of card. The entries are white blood cell counts (1000 cells/μL) and heights (inches) from male subjects examined as part of a large study conducted by a health organization. The data are matched, so that the first subject has a white blood cell count of 8.7 and a height of 70.8, and so on. Given the context of the data in the table, what issue can be addressed by conducting a statistical analysis of the measurements? Choose the correct answer below. A. Is there a relationship between the mean white blood cell count and the mean heighth? B. Is there a relationship or an association between white blood cell countand height? C. Does a change in height cause white blood cell count to increase or decrease? D. Does a change in white blood cell count cause height to increase or decrease? E. No conclusion can be drawn from the data.
B. Is there a relationship or an association between white blood cell count and height?
1.3.15 For the following scenario, identify which of these types of sampling is used: random, systematic, convenience, stratified, or cluster. A researcher collects sample data by selecting every 35th hospital employee on an alphabetical list of all hospital employees Choose the correct answer below. A. Cluster B. Systematic C. Convenience D. Random E. Stratified
B. Systematic
1.3.9 Identify the type of sampling used (random, systematic, convenience, stratified, or cluster sampling) in the situation described below. A researcher selects every 957th social security number and surveys the corresponding person. Which type of sampling did the researcher use? A. Stratified sampling B. Systematic sampling C. Cluster sampling D. Convenience sampling RandomRandom sampling
B. Systematic sampling
1.2.21 For the given description of data, determine which of the four levels of measurement (nominal, ordinal, interval, ratio) is most appropriate. Level of pain on a scale of 1 to 10 Choose the correct answer below. A. The nominal level of measurement is most appropriate because the data cannot be ordered. B. The ordinal level of measurement is most appropriate because the data can be ordered, but differences (obtained by subtraction) cannot be found or are meaningless. C. The ratio level of measurement is most appropriate because the data can be ordered, differences (obtained by subtraction) can be found and are meaningful, and there is a natural zero starting point. D. The interval level of measurement is most appropriate because the data can be ordered, differences (obtained by subtraction) can be found and are meaningful, but there is no naturalbut there is no natural zero starting point
B. The ordinal level of measurement is most appropriate because the data can be ordered, but differences (obtained by subtraction) cannot be found or are meaningless.
1.2.25 For the given description of data, determine which of the four levels of measurement (nominal, ordinal, interval, ratio) is most appropriate. A research project on the effectiveness of pacemaker insertions begins with a compilation of the number of of pacemaker insertions performed at each hospital in a country. Choose the correct answer below. A. The interval level of measurement is most appropriate because the data can be ordered , differences (obtained by subtraction) can be found and are meaningful, but there is no natural zero starting point. B. The ratio level of measurement is most appropriate because the data can be ordered, differences differences (obtained by subtraction) can be found and are meaningful , and there is a natural zero starting point C. The nominal level of measurement is most appropriate because the data cannot be ordered. D. The ordinal level of measurement is most appropriate because the data can be ordered , but differences (obtained by subtraction) cannot be found or are meaningless
B. The ratio level of measurement is most appropriate because the data can be ordered, differences differences (obtained by subtraction) can be found and are meaningful , and there is a natural zero starting point
1.1.7 Determine whether the given source has the potential to create a bias in a statistical study. A data set includes brain volumes from 10 pairs of monozygotic (identical) twins. The data were collected by researchers at Harvard University, Massachusetts General Hospital, Dartmouth College, and the University of California at Davis. Choose the correct answer below. A. There does appear to be a potential to create a bias. There is an incentive to produce results that are in line with the organizations' creed and that of their funders. B. There does not appear to be a potential to create a bias. The organizations would not gain from putting a spin on the results. C. There does appear to be a potential to create a bias. There is an incentive to make the results statistically insignificant. D. There does not appear to be a potential to create a bias. The organizations are reputable and have many professional and credible members.
B. There does not appear to be a potential to create a bias. The organizations would not gain from putting a spin on the results.
1.1.RA-9 Which of the following would NOT cast doubt on the usefulness of sample data? Choose the correct answer below A. missing data B. an effective sampling method C. nonresponse D. Order of questions in a survey
B. an effective sampling method
What term is used for the technique in which the subject doesn't know whether he or she is receiving a treatment or a placebo.
Blinding
What type of sampling involves the division of the population area into sections (or clusters); randomly selecting some of those clusters; choosing all members from selected clusters
Cluster Sampling
1.2.33 Determine whether the given value is from a discrete or continuous data set. When a car is randomly selected, it is found to have a gas tank that can hold 17.9 gal Choose the correct answer below. A. A discrete data set because there are infinitely many possible values and those values can be counted. B. A discrete data set because there are a finite number of possible values. C. A continuous data set because there are infinitely many possible values and those values cannot be counted. D. The data set is neither continuous nor discrete.
C. A continuous data set because there are infinitely many possible values and those values cannot be counted.
1.3.15 For the following scenario, identify which of these types of sampling is used: random, systematic, convenience, stratified, or cluster. A researcher collects sample data by selecting the first 60 hospital employees that the researcher encounters at the hospital's main entrance. Choose the correct answer below. A. Cluster B. Systematic C. Convenience D. Random E. Stratified
C. Convenience
1.3.19 For the following scenario, identify which of these types of sampling is used: random, systematic, convenience, stratified, or cluster. A medical student collects sample data on dietary habits among females in her state by surveying all of the females she encounters in the nearby cars during her commute to school during one week Choose the correct answer below. A. Cluster B. Systematic C. Convenience D. Random E. Stratified
C. Convenience
1.1.21 Refer to the accompanying data table on back of card. The entries are brain volume (cm3) and arm circumference circumferences (inches) from male subjects examined as part of a large study conducted by a health organization. The data are matched, so that the first subject has a brain volume of 1005 and an arm circumference of 31.9, and so on. Given that the data are matched and considering the units of the data, does it make sense to use the difference between each brain volumebrain volume and the corresponding arm circumferencearm circumference? Why or why not? Choose the correct answer below. A. Yes, it does make sense to use the difference between each brain volumebrain volume and the corresponding arm circumferencearm circumference, because they are measurements obtained from the same person. B. No, it does not make sense to use the difference between each brain volumebrain volume and the corresponding arm circumferencearm circumference, because the terms should be added. C. No, it does not make sense to use the difference between each brain volumebrain volume and the corresponding arm circumferencearm circumference, because these measure different quantities with different units. D. Yes, it does make sense to use the difference between each brain volumebrain volume and the corresponding arm circumferencearm circumference, because there is a clear relationship between brain volumebrain volume and arm circumferencearm circumference.
C. No, it does not make sense to use the difference between each brain volumebrain volume and the corresponding arm circumferencearm circumference, because these measure different quantities with different units.
1.1.3 When testing a new treatment, what is the difference between statistical significance and practical significance? Can a treatment have statistical significance, but not practical significance? Choose the correct answer below. A. Statistical significance is achieved when the result is very unlikely to occur by chance. Practical significance is related to whether common sense suggests that the treatment makes enough of a difference to justify its use. It is not possible for a treatment to have statistical significance, but not practical significance. B. Statistical significance is related to whether common sense suggests that the treatment makes enough of a difference to justify its use. Practical significance is achieved when the result is very unlikely to occur by chance. It is possible for a treatment to have statistical significance, but not practical significance. C. Statistical significance is achieved when the result is very unlikely to occur by chance. Practical significance is related to whether common sense suggests that the treatment makes enough of a difference to justify its use. It is possible for a treatment to have statistical significance, but not practical significance. D. Statistical significance is related to whether common sense suggests that the treatment makes enough of a difference to justify its use. Practical significance is achieved when the result is very unlikely to occur by chance. It is not possible for a treatment to have statistical significance, but not practical significance.
C. Statistical significance is achieved when the result is very unlikely to occur by chance. Practical significance is related to whether common sense suggests that the treatment makes enough of a difference to justify its use. It is possible for a treatment to have statistical significance, but not practical significance.
1.1.19 Refer to the sample of body temperatures (degrees Fahrenheit) in the table on back of card. Given these temperatures, what issue can be addressed by conducting a statistical analysis of the data? Subject Choose the correct answer below. A. The data can be used to find the percentage of people whose body temperature increases with illness. B. The data can be used to address the issue of whether there is a correlation between average body temperature and a person's exposure to sunlight. C. The data can be used to address the issue of whether there is a correlation between body temperatures at 8 AM and at 12 AM. D. The data can be used to address the issue of whether there is a difference between average body temperature for males and for females.
C. The data can be used to address the issue of whether there is a correlation between body temperatures at 8 AM and at 12 AM.
1.2.21 For the given description of data, determine which of the four levels of measurement (nominal, ordinal, interval, ratio) is most appropriate. Blood type (A, B, AB, O) Choose the correct answer below. A. The interval level of measurement is most appropriate because the data can be ordered , differences (obtained by subtraction) can be found and are meaningful, but there is no natural zero starting point. B. The ratio level of measurement is most appropriate because the data can be ordered, differences differences (obtained by subtraction) can be found and are meaningful , and there is a natural zero starting point C. The nominal level of measurement is most appropriate because the data cannot be ordered. D. The ordinal level of measurement is most appropriate because the data can be ordered , but differences (obtained by subtraction) cannot be found or are meaningless
C. The nominal level of measurement is most appropriate because the data cannot be ordered.
1.2.23 For the given description of data, determine which of the four levels of measurement (nominal, ordinal, interval, ratio) is most appropriate. Gender of subject Choose the correct answer below. A. The interval level of measurement is most appropriate because the data can be ordered , differences (obtained by subtraction) can be found and are meaningful, but there is no natural zero starting point. B. The ratio level of measurement is most appropriate because the data can be ordered, differences differences (obtained by subtraction) can be found and are meaningful , and there is a natural zero starting point C. The nominal level of measurement is most appropriate because the data cannot be ordered. D. The ordinal level of measurement is most appropriate because the data can be ordered , but differences (obtained by subtraction) cannot be found or are meaningless
C. The nominal level of measurement is most appropriate because the data cannot be ordered.
1.2.25 For the given description of data, determine which of the four levels of measurement (nominal, ordinal, interval, ratio) is most appropriate. A research project on the effectiveness of skin grafts begins with a compilation of the hospitals that provide skin grafts Choose the correct answer below. A. The interval level of measurement is most appropriate because the data can be ordered , differences (obtained by subtraction) can be found and are meaningful, but there is no natural zero starting point. B. The ratio level of measurement is most appropriate because the data can be ordered, differences differences (obtained by subtraction) can be found and are meaningful , and there is a natural zero starting point C. The nominal level of measurement is most appropriate because the data cannot be ordered. D. The ordinal level of measurement is most appropriate because the data can be ordered , but differences (obtained by subtraction) cannot be found or are meaningless
C. The nominal level of measurement is most appropriate because the data cannot be ordered.
What type of data result from an infinitely large number of possible values that correspond to some continuous scale that covers a range of values without gaps, interruptions, or jumps
Continuous (numerical) data
what type of sampling uses results that are easy to get
Convenience Sampling
In what type of study are data are observed, measured, and collected at one point in time
Cross sectional study
1.1.9 Determine whether the sampling method described below appears to be sound or is flawed. In a survey of 548548 subjects, each was asked how often he or she read a book.read a book. The survey subjects were internet users who responded to a question that was posted on a news website. Choose the correct answer below. A. It appears to be sound because the data are not biased in any way. B. It is flawed because it is not statistically significant. C. It is flawed because it is a census. D. It is flawed because it is a voluntary response sample.
D. It is flawed because it is a voluntary response sample.
1.2.11 Determine whether the given value is a statistic or a parameter. A sample of students is selected and it is found that 35% own a computer. Choose the correct statement below. A. Statistic because the value is a numerical measurement describing a characteristic of a population. B. Parameter because the value is a numerical measurement describing a characteristic of a population. C. Parameter because the value is a numerical measurement describing a characteristic of a sample. D. Statistic because the value is a numerical measurement describing a characteristic of a sample.
D. Statistic because the value is a numerical measurement describing a characteristic of a sample.
1.2.25 For the given description of data, determine which of the four levels of measurement (nominal, ordinal, interval, ratio) is most appropriate. A research project on the effectiveness of liver transplants begins with national rankings of the hospitals that provide liver transplants. Choose the correct answer below. A. The interval level of measurement is most appropriate because the data can be ordered , differences (obtained by subtraction) can be found and are meaningful, but there is no natural zero starting point. B. The ratio level of measurement is most appropriate because the data can be ordered, differences differences (obtained by subtraction) can be found and are meaningful , and there is a natural zero starting point C. The nominal level of measurement is most appropriate because the data cannot be ordered. D. The ordinal level of measurement is most appropriate because the data can be ordered , but differences (obtained by subtraction) cannot be found or are meaningless
D. The ordinal level of measurement is most appropriate because the data can be ordered , but differences (obtained by subtraction) cannot be found or are meaningless
1.1.8 An article noted that chocolate is rich in flavonoids. The article reports that "regular consumption of foods rich in flavonoids may reduce the risk of coronary heart disease." The study received funding from a candy company and a chocolate manufacturers association. Identify and explain at least one source of bias in the study described. Then suggest how the bias might have been avoided. Choose the correct answer below. A. Since the sample is self-selected, there is a definite participation bias in this study. The researchers should randomly select the subjects of the study. B. The data do not seem to support the claims being made by the article. The article's author should consult an expert to make sure that he or she is correctly interpreting the study's results. C. The questions used in the study might have caused the respondents to give inaccurate or dishonest responses. The question wording should be changed to be more neutral. D. The researchers may have been more inclined to provide favorable results because funding was provided by a party with a definite interest. The bias could have been avoided if the researchers were not paid by the candy company and the chocolate manufacturers
D. The researchers may have been more inclined to provide favorable results because funding was provided by a party with a definite interest. The bias could have been avoided if the researchers were not paid by the candy company and the chocolate manufacturers
1.1.5 Determine whether the source given below has the potential to create a bias in a statistical study. A certain medical organization tends to oppose the use of meat and dairy products in our diets, and that organization has received hundreds of thousands of dollars in funding from an animal rights foundation. Choose the correct answer below. A. There does not appear to be a potential to create a bias. The organization is reputable and has many professional and credible members. B. There does not appear to be a potential to create a bias. The organization would not gain from putting spin on the results. C. There does appear to be a potential to create a bias. There is an incentive to make the results statistically insignificant. D. There does appear to be a potential to create a bias. There is an incentive to produce results that are in line with the organization's creed and that of its funders.
D. There does appear to be a potential to create a bias. There is an incentive to produce results that are in line with the organization's creed and that of its funders.
1.1.RA-7 Which of the following is not a misuse of statistics? Choose the correct answer below A. misleading graphs B. making conclusions about a population based on a voluntary response sample C. concluding that a variable causes another variable because they have some correlation D. utilizing valid statistical methods and correct sampling techniques
D. utilizing valid statistical methods and correct sampling techniques
What are collections of observations (such as measurements, genders, survey responses) called?
Data
what type of data result when the number of possible values is either a finite number or a 'countable' number (i.e. the number of possible values is 0, 1, 2, 3, . . .) Example: The number of eggs that a hen lays
Discrete data
What term is used for a study where: (1) The subject doesn't know whether he or she is receiving the treatment or a placebo (2) The experimenter does not know whether he or she is administering the treatment or placebo
Double-blind
1.3.19 For the following scenario, identify which of these types of sampling is used: random, systematic, convenience, stratified, or cluster. A medical student collects sample data on dietary habits among female cancer patients in her city by randomly selecting 7777 female cancer patients from each of the education categories of less than bachelor's degree, bachelor's degree, and greater than bachelor's degree Choose the correct answer below. A. Cluster B. Systematic C. Convenience D. Random E. Stratified
E. Stratified
What level of measurement is like the ordinal level, with the additional property that the difference between any two data values is meaningful, however, there is no natural zero starting point (where none of the quantity is present) Example: Years 1000, 2000, 1776, and 1492
Interval level of measurement
What level of measurement is characterized by data that consist of names, labels, or categories only, and the data cannot be arranged in an ordering scheme (such as low to high) Example: Survey responses yes, no, undecided
Nominal level of measurement
what type of error occurs when sample data is incorrectly collected, recorded, or analyzed (such as by selecting a biased sample, using a defective instrument, or copying the data incorrectly)
Nonsampling error
What type of study involves observing and measuring specific characteristics WITHOUT ATTEMPTING TO MODIFY the subjects being studied
Observational study
1.1.1 A newspaper posted this question on its website:" how often do you seek medical information online?" Of one thousand and seventy two Internet users who chose to respond, 38% of them responded with "frequently". What term is used to describe this type of survey in which the people surveyed consists of those who decided to respond? What is wrong with this type of sampling method? Part 1: What term is used to describe this type of survey? Select all that apply A. The respondents are a population. B. The respondents are a self-selected sample. C. The respondents are a census. D. The respondents are a voluntary response sample. Part 2: What is wrong with this type of sampling method? Select all that apply. A. it is too expensive. B. Many people may choose not to respond to the survey. C. It is too time consuming. D. Responses may not reflect the opinions of the general population. E. The survey question is "loaded," or intentionally worded to elicit a desired response.
Part 1: A. The respondents are a population. D. The respondents are a voluntary response sample. Part 2: B. Many people may choose not to respond to the survey. D. Responses may not reflect the opinions of the general population.
1.2.1 In a survey of all 59 mid-level managers of a biotech firm, 46% said that they wash their hands after attending a sporting event. A. Identify the sample and the population. B. Is the value of 46% a statistic or a parameter? Part A-a: Identify the population. Choose the correct answer below. a. all people who wash their hands after attending a sporting event b. all 59 mid-level managers surveyed c. all mid-level managers d. all adults e. all people Part A-b: Identify the sample. Choose the correct answer below. a. all mid-level managers b. all adults c. all 59 mid-level managers surveyed d. all people e. all people who wash their hands after attending a sporting event Part B: Is the value of 46% a statistic or a parameter? a. The given value is a parameter because the numerical measurement describes a characteristic of a population. b. The given value is a statistic because the numerical measurement describes a characteristic of a sample. c. The given value is a parameter because the numerical measurement describes a characteristic of a sample. d. The given value is a statistic because the numerical measurement describes a characteristic of a population.
Part A-a= b. all 59 mid-level managers surveyed Part A-b= c. all 59 mid-level managers surveyed Part B= a. The given value is a parameter because the numerical measurement describes a characteristic of a population.
1.2.1 In a survey of 1774 adults in New England, 44% said that they wash their hands after attending a sporting event. a. Identify the sample and the population. b. Is the value of 44% a statistic or a parameter? Part A-a: Identify the population. Choose the correct answer below. a. all people b. all people who wash their hands after attending a sporting event c. all adults d. all adults in New England e. the 1774 adults surveyed Part A-b: Identify the sample. Choose the correct answer below. a. all adults b. all people who wash their hands after attending a sporting event c. all adults in New England d. the 1774 adults surveyed e. all people Part B: Is the value of 44% a statistic or a parameter? a. The given value is a parameter because the numerical measurement describes a characteristic of a sample. b. The given value is a parameter because the numerical measurement describes a characteristic of a population. c. The given value is a statistic because the numerical measurement describes a characteristic of a sample. d. The given value is a statistic because the numerical measurement describes a characteristic of a population.
Part A-a= d. all adults in New England Part A-b= d. the 1774 adults surveyed Part B= c. The given value is a statistic because the numerical measurement describes a characteristic of a sample.
What type of sample involves selecting members from a population in such a way that each member of the population has a known (but not necessarily the same) chance of being selected
Probability Sample
What type of data consists of numbers representing counts or measurements. Example: The weights of supermodels Example: The ages of respondents
Quantitative (or numerical) data
What kind of sample involves selecting members from the population that are selected in such a way that EACH INDIVIDUAL MEMBER in the population has an equal chance of being selected
Random Sample
What term is used when subjects are assigned to different groups through a process of random selection. The logic is to use chance as a way to create two groups that are similar.
Randomization
What level of measurement is the same as the interval level but with the additional property that there is also a natural zero starting point (where zero indicates that none of the quantity is present); for values at this level, differences and ratios are meaningful Example: Prices of college textbooks ($0 represents no cost, a $100 book costs twice as much as a $50 book)
Ratio level of measurement
In what types of study are data collected from the past by going back in time (examine records, interviews, ...)
Retrospective (or case control) study
Fill in the blank If we are collecting sample data for a study, the __________ that we choose can greatly influence the validity of our conclusions. For example, we can use sound statistical methods to analyze Data in voluntary response samples, but the results are not necessarily valid.
Sampling method
What type of sample is of n (a specific number) subjects selected in such a way that every possible SAMPLE OF THE SAME SIZE n has the same chance of being chosen.
Simple Random Sample
In an American optometrist association survey, 1009 adults where randomly selected and asked to identify What they worry most about losing. 51% of the respondents chose vision. What is wrong with this?
The survey sponsor, American optometry Association, has the potential to gain from the results, which raises doubts about the objectivity of the results
Success in the introductory statistics course typically requires more __________ __________ than mathematical expertise
common sense
Define Statistics
is the science of planning studies and experiments, obtaining data, and then organizing, summarizing, presenting, analyzing, interpreting, and drawing conclusions based on the data
What sampling method involves collecting data by using some combination of the basic sampling methods In this sampling design, pollsters select a sample in different stages, and each stage might use different methods of sampling
multistage sampling
Sample data must be collected in an appropriate way, such as through a process of __________ selection.
random