Lesson 3.1 Content Check
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Last updated over 1 year ago
16 questions
Required
6
- How many quarters equal $10?
- How tall are the elm trees on Elm Street?
- How tall is the elm tree in Laura’s backyard?
- What proportion of Texas residents would choose vanilla as their favorite ice cream flavor?
- What is the governor’s favorite ice cream flavor?
- How much money do high school students carry with them?
- Statistical Question
- Non-statistical Question
6
Categorize the studies:
Categorize the studies:
- Among a group of disabled women aged 65 and older who were tracked for several years, those who had a vitamin B12 deficiency were twice as likely to suffer severe depression as those who did not. (American Journal of Psychology 157 [2000]: 715)
- The leg muscles of men aged 60 to 75 were 50% to 80% stronger after they participated in a 16‐week, high‐intensity resistance‐training program twice a week. (Journal of Gerontology 55A [2000}: B336)
- Over a 4‐month period, among 30 people with bipolar disorder, patients who were given a high dose (10g/day) of omega‐3 fats from fish oil improved more than those given a placebo. (Archives of General Psychiatry 56 [1999]: 407)
- Observational Study
- Experiment
6
Categorize the studies:
Categorize the studies:
- In 2002, the journal Science reported that a study of women in Finland indicated that having sons shortened the lifespan of mothers by about 34 weeks per son, but that daughters helped to lengthen the mothers’ lives. The data came from church records from the period 1640 to 1870.
- Some gardeners prefer to use nonchemical methods to control insect pests in their gardens. Researchers have designed two kinds of traps, and want to know which design will be more effective. They randomly choose 10 locations in a large garden and place one of each kind of trap at each location. After a week, they count the number of bugs in each trap.
- In 2001 a report in the Journal of the American Cancer Institute indicated that women who work at nights have a 60% greater risk of developing breast cancer. Researchers based these findings on the work histories of 763 women with breast cancer and 741 women without the disease.
- Experimental Study
- Observational Study
6
Categorize the following studies (all are observational) as Retrospective(looking back) or Prospective(looking forward):
Categorize the following studies (all are observational) as Retrospective(looking back) or Prospective(looking forward):
- The leg muscles of men aged 60 to 75 were measured at the beginning of a study. The leg muscles were found to be 50% to 80% stronger after they participated in a 16‐week, high‐intensity resistance‐training program twice a week. (Journal of Gerontology 55A [2000}: B336)
- A group of disabled women aged 65 and older were tracked for several years, those who had a vitamin B12 deficiency were twice as likely to suffer severe depression as those who did not. (American Journal of Psychology 157 [2000]: 715)
- A recent study in Europe looked at a large group of women of childbearing age. The researchers asked each woman how much alcohol they had consumed over the past 12 months. The researchers found that women who drank moderate amounts of alcohol were somewhat less likely to have infertility than women who did not. (November, 2001).
- Restrospective Observational Study
- Prospective Observational Study
Required
2
Each week, the Gallup Poll surveys about 1500 adult U.S. residents to determine current opinions on a wide variety of issues. Identify the population and sample in this setting.
Each week, the Gallup Poll surveys about 1500 adult U.S. residents to determine current opinions on a wide variety of issues. Identify the population and sample in this setting.
Required
2
A large retailer prepares its customers’ monthly credit card bills using a machine that folds the bills, stuffs them into envelopes, and seals the envelopes for mailing. Are the envelopes completely sealed? Inspectors choose 40 envelopes at random from the 1000 stuffed each hour for visual inspection. Identify the population and sample in this setting.
A large retailer prepares its customers’ monthly credit card bills using a machine that folds the bills, stuffs them into envelopes, and seals the envelopes for mailing.
Are the envelopes completely sealed?
Inspectors choose 40 envelopes at random from the 1000 stuffed each hour for visual inspection. Identify the population and sample in this setting.
Required
2
How much vitamin C does a popular brand of orange juice contain? A nutrition magazine measures the amount of vitamin C in 50 half-gallon containers of a popular brand of orange juice from 10 different grocery stores and concludes that the containers produced by this company do not have as much vitamin C as advertised. Identify the population and sample in this setting.
How much vitamin C does a popular brand of orange juice contain?
A nutrition magazine measures the amount of vitamin C in 50 half-gallon containers of a popular brand of orange juice from 10 different grocery stores and concludes that the containers produced by this company do not have as much vitamin C as advertised.
Identify the population and sample in this setting.
Required
1
Required
2
Some gardeners prefer to use nonchemical methods to control insect pests in their gardens. Researchers have designed two kinds of traps, and want to know which design will be more effective. They randomly choose 10 locations in a large garden and place one of each kind of trap at each location. After a week, they count the number of bugs in each trap.
Is this an observational study or an experiment?
Some gardeners prefer to use nonchemical methods to control insect pests in their gardens. Researchers have designed two kinds of traps, and want to know which design will be more effective. They randomly choose 10 locations in a large garden and place one of each kind of trap at each location. After a week, they count the number of bugs in each trap.
Is this an observational study or an experiment?
Required
2
Some people who race greyhounds give the dogs large doses of Vitamin C in the belief that the dogs will run faster. Investigators at the University of Florida tried three different diets in random order on each of five racing greyhounds. They were surprised to find that when the dogs ate high amounts of Vitamin C they ran more slowly.
Is this an observational study or an experiment?
Some people who race greyhounds give the dogs large doses of Vitamin C in the belief that the dogs will run faster. Investigators at the University of Florida tried three different diets in random order on each of five racing greyhounds. They were surprised to find that when the dogs ate high amounts of Vitamin C they ran more slowly.
Is this an observational study or an experiment?
Required
2
A recent study in Europe looked at a large group of 350 women of childbearing age. The researchers asked each woman how much alcohol they had consumed over the past 12 months. The researchers found that women who drank moderate amounts of alcohol were somewhat less likely to have infertility than women who did not.Select the population and the sample.
A recent study in Europe looked at a large group of 350 women of childbearing age. The researchers asked each woman how much alcohol they had consumed over the past 12 months. The researchers found that women who drank moderate amounts of alcohol were somewhat less likely to have infertility than women who did not.
Select the population and the sample.
Required
1
A department store mails a customer-satisfaction survey to people who make credit card purchases at the store. This month, 45,000 people made credit card purchases. Surveys are mailed to 1000 of these people, chosen at random, and 137 people return the survey form.
Identify the population and sample in this setting. Read carefully!
A department store mails a customer-satisfaction survey to people who make credit card purchases at the store. This month, 45,000 people made credit card purchases. Surveys are mailed to 1000 of these people, chosen at random, and 137 people return the survey form.
Identify the population and sample in this setting. Read carefully!
Required
4
The band director at a high school wants to know what percentage of parents supports a decrease in the budget for fine arts. Because many parents attend the school’s annual musical, the director surveys the first 30 parents who arrive at the show. Explain why this sampling method is biased. Choose all the correct answers.
The band director at a high school wants to know what percentage of parents supports a decrease in the budget for fine arts. Because many parents attend the school’s annual musical, the director surveys the first 30 parents who arrive at the show.
Explain why this sampling method is biased.
Choose all the correct answers.
Required
2
The band director at a high school wants to know what percentage of parents supports a decrease in the budget for fine arts. Because many parents attend the school’s annual musical, the director surveys the first 30 parents who arrive at the show.
Is the proportion of parents in the sample who support the decrease likely greater than or less than the proportion of all parents in the school who support the decrease?
The band director at a high school wants to know what percentage of parents supports a decrease in the budget for fine arts. Because many parents attend the school’s annual musical, the director surveys the first 30 parents who arrive at the show.
Is the proportion of parents in the sample who support the decrease likely greater than or less than the proportion of all parents in the school who support the decrease?
Required
3
The quality-control department at an automobile factory checks the tightness of motor-mounting bolts installed by assembly-line workers by sampling the first 25 cars produced by the assembly line each day. Explain why this sampling method is biased.
The quality-control department at an automobile factory checks the tightness of motor-mounting bolts installed by assembly-line workers by sampling the first 25 cars produced by the assembly line each day.
Explain why this sampling method is biased.
Required
2
The quality-control department at an automobile factory checks the tightness of motor-mounting bolts installed by assembly-line workers by sampling the first 25 cars produced by the assembly line each day. Is this method likely to overestimate or underestimate the proportion of bolts that are improperly tightened?Why?
The quality-control department at an automobile factory checks the tightness of motor-mounting bolts installed by assembly-line workers by sampling the first 25 cars produced by the assembly line each day.
Is this method likely to overestimate or underestimate the proportion of bolts that are improperly tightened?
Why?