Stats Chapter 1
How do parameter and statistic differ?
A parameter is a numerical measurement of a population; a statistic is a numerical measurement of a sample.
How do parameter and a statistic differ?
A parameter is an numerical measurement of a population; a statistic is a numerical measurement of a sample.
What is a voluntary response sample?
A sample in which the subjects themselves decide whether to be included in the study.
Which sampling method divides the population up into sections, randomly selects some of those sections, then chooses all the members from the selected sections to study?
Cluster
Which sampling method divides the population up into sections, randomly selects some of those sections, then chooses all the members from the selected sections to study?
Cluster
incorrect, 1.4.9 Identify the type of sampling used (random, systematic, convenience, stratified, or cluster sampling) in the situation described below. A woman is selected by a marketing company to participate in a paid focus group. The company says that the woman was selected because everyone in four randomly selected towns was being selected. nothing nothing
Cluster
Which of the following is NOT a level of measurement?
Quantitative
A quality control engineer selects every 15 comma 000 th light bulb that is produced.
The sample is not a simple random sample because every sample of the same size does not have the same chance of being selected.
Determine whether the sample described below is a simple random sample. A quality control engineer selects every 5000th can opener that is produced.
The sample is not a simple random sample because every sample of the same size does not have the same chance of being selected.
Determine whether the given value is a statistic or a parameter. A study was conducted of all 2281 car owners in a certain country.
The value is a parameter because it is a numerical measurement describing some characteristic of a population.
Determine whether the given value is a statistic or a parameter. Upper A sample of 1116 adults showed that 6 % were optimistic.
The value is a statistic because it is numerical measurement describing some characteristic of a sample.
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.
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.
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 a chance of being selected.
What is the difference between a random sample and a simple random sample?
With a random sample, each individual has the same change of being selected. With a simple random sample, all samples of the same size have the same chance of being selected.
Which of the following is typically the least important factor to consider when conducting a statistical analysis of data?
Formula Calculation
Which of the following is typically the least important factor to consider when conducting a statistical analysis of data?
Formula calculation
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 weight of 1815.6 kg.
IT is from a continuous data set because the number of possible values is infinite and not countable.
Determine whether the results below appear to have statistical significance, and also determine whether the results have practical significance. In a study of a weight loss program, 7 subjects lost an average of 43 lbs. It is found that there is about a 35% chance of getting such results with a diet that has no effect. a. Does the weight loss program have statistical significance? b. Does the weight loss program have practical significance?
No, the program is not statistically significant because the results are likely to occur by chance. b. Yes, the program is practically significant because the amount of lost weight is large enough to be considered practically significant.
Determine which of the four levels of measurement (nominal, ordinal, interval, ratio) is most appropriate. Positions of runners in a race
Ordinal
Determine which of the four levels of measurement (nominal, ordinal, interval, ratio) is most appropriate. Placements of swimmers in a swim meet
Ordinal
Determine whether the description corresponds to an observational study or an experiment. Fifty patients with colon cancer are divided into two groups. One group receives an experimental drug to fight cancer comma the other a placebo. After one year comma the spread of the cancer is measured.
Experiment
The data in table 1 are the weights (in kilograms) of freshman students. The x-values are weights measured in September and the y-values are their corresponding weights measured in April of the following spring. The x-values in table 2 are nicotine amounts (in mg) in different 100 mm filtered, non-"light" menthol cigarettes. The y-values in table 2 are nicotine amounts (in mg) in different king-size nonfiltered, nonmenthol, and non-"light" cigarettes. In data table 2, is each x-value matched with a corresponding y-value, as in data table 1? That is, is each x-value associated with the corresponding y-value in some meaningful way? In table 2, does it make sense to use the difference between each x-value and the y-value that is in the same column?
In table 2, is each x-value associated with the corresponding y-value in some meaningful way? No Does it make sense to use the difference between each x-value and the y-value that is in the same column? No
Determine whether the sampling method described below appears to be sound or is flawed. In a survey of 686 subjects, each was asked how often he or she read a book. The survey subjects were internet users who responded to a question that was posted on a news website.
It is flawed because it is a voluntary response sample.
Determine whether the sampling method described below appears to be sound or is flawed. In a survey of 607 subjects, each was asked how often he or she played sports. The survey subjects were internet users who responded to a question that was posted on a news website.
It is flawed because it is a voluntary response sample.
Determine whether the given value is from a discrete or continuous data set. When a can is randomly selected, it is found to have 2 doors.
It is from a discrete data set because the number of possible values is finite or countable.
Several studies showed that after drinking red wine, subjects had increased blood levels of antioxidants. Antioxidants have been associated with decreased risk of heart disease. A wine company financed this research. What is wrong with this study?
Self-Interest study
Several studies showed that after eating chocolate, subjects had increased blood levels of antioxidants. Antioxidants have been associated with decreased risk of heart disease. A candy company financed this research. What is wrong with this study?
Self-interest study
Identify the level of measurement of the data, and explain what is wrong with the given calculation. In a survey, the responses of respondents are identified as 1 for a "yes" comma 2 for a "no" comma 3 for a "maybe" comma and 4 for anything else. The average (mean) is calculated for 621 respondents and the result is 1.5 .
Such data are not counts or measures of anything, so it makes no sense to compute their average (mean).
Identify the type of sampling used (random, systematic, convenience, stratified, or cluster sampling) in the situation described below. A man is selected by a marketing company to participate in a paid focus group. The company says that the man was selected because every 2500th person in the phone number listings was being selected.
Systematic sampling
A polling company reported that 29% of 1018 surveyed adults said that cellular phones are "very harmful." Complete parts (a) through (d) below. a. what is the exact value that is 29& of 1018? b. Could the result from part (a) be the actual number of adults who said that cellular phones are "very harmful" question mark Why or why not? c. what could be the actual number of adults who said that cellular phones are "very harmful"? d. Among the 1018 respondents, 606 said that cellular phones are "not at all harmful" what percentage of respondents said that cellular phones are "not at all harmful"?
a. 295.22 b. No, the result from part (a) could not be the actual number of adults who said that cellular phones are "very harmful" because a count of people must result in a whole number. c. The actual number of adults with this opinion could be 295. d. 59.53%
The data in table 1 are the weights (in kilograms) of freshman students. The x-values are weights measured in September and the y-values are their corresponding weights measured in April of the following spring. The x-values in table 2 are nicotine amounts (in mg) in different 100 mm filtered, non-"light" menthol cigarettes. The y-values in table 2 are nicotine amounts (in mg) in different king-size nonfiltered, nonmenthol, and non-"light" cigarettes. In data table 2, is each x-value matched with a corresponding y-value, as in data table 1? That is, is each x-value associated with the corresponding y-value in some meaningful way? In table 2, does it make sense to use the difference between each x-value and the y-value that is in the same column?
a. No b.No
Determine whether the results below appear to have statistical significance, and also determine whether the results have practical significance. In a study of a weight loss program, 4 subjects lost an average of 45 lbs. It is found that there is about a 39% chance of getting such results with a diet that has no effect. a. Does the weight loss program have statistical significance? b. Does the weight loss program have practical significance?
a. No, the program is not statistically significant because the results are likely to occur by chance. b. Yes, the program is practically significant because the amount of lost weight is large enough to be considered practically significant.
A polling company reported that 47% of 1013 surveyed adults said that cellular phones are "quite annoying." Complete parts (a) through (d) below. a, what is the exact value that is 47% of 1013? b. Could the result from part(a) be the actual number of adults who said that cellular phones are "quite annoying"? Why or why not? c. What could be the actual number of adults who said that cellular phones are "quite annoying"? d. Among the 1013 respondents, 91 said that cellular phones are "not at all annoying." What percentage of respondents said that cellular phones are "not at all annoying"?
a. the exact value is 476.11 b. No, the result from part (a) could not be the actual number of adults who said that cellular phones are "quite annoying" in a whole number. c. The actual number of adults with this opinion could be 476. d. 8.98%
Identify the type of observational study. A researcher plans to obtain data by interviewing spouses of victims who perished in a bombing to see how they' re coping now?
cross-sectional
Determine whether the description corresponds to an observational study or an experiment. Eighty patients with stomach cancer are divided into two groups. One group receives an experimental drug to fight cancer comma the other a placebo. After one year comma the spread of the cancer is measured.
experiment
Identify the level of measurement of the data, and explain what is wrong with the given calculation. In a survey, the favorite sports of respondents are identified as 100 for basketball, 200 for baseball, 300 for football, and 400 for anything else. The average (mean) is calculated for 610 respondents and the result us 256.1
nominal Such data are not counts or measures of anything, so it makes no sense to compute their average (mean).
Identify the type of observational study. A researcher plans to obtain data by interviewing spouses of victims who perished in a bombing. He will interview them comma and people unrelated to the victims comma over the next 10 nbsp years to see how closeness to a traumatic event might affect recovery time.
prospective
Which of the following is not a level of measurement? ordinal ratio nominal quantitative
quantitative
