Solution: In Exercises 920, identify which of these types of sampling is used: random

Simple Random Sample At a national conference of the American Applicances Association, a market researcher plans to conduct a survey of conference attendees. She uses the list of attendee names and selects every 20th name. Is the result a simple random sample? Why or why not? In general, what is a simple random sample?

Observational Study and Experiment You want to conduct a study to determine whether fruit consumption leads to reduced weight. Why would an experiment be better than an observational study?

Simple Random Convenience Sample A student of the author listed his adult friends, and then he surveyed a simple random sample of them. What is the population from which the simple random sample was selected? Are the results likely to be representative of the general population of adults in the United States? Why or why not?

Convenience Sample The author conducted a survey of the students in all of his classes. He asked the students to indicate whether they are lefthanded or righthanded. Is this convenience sample likely to provide results that are typical of the population? Are the results likely to be good or bad? Does the quality of the results in this survey reflect the quality of convenience samples in general?

In Exercises 58, determine whether the given description corresponds to an observational study or an experiment. In each case, give a brief explanation of your choice.Contentious Survey The Milgram Research Company wants to study reactions to stress, so it administers surveys in which the person asking the questions pretends to become very angry with the survey subject. At one point, the surveyor screams at the subject and asks how anyone could have such stupid opinions

In Exercises 58, determine whether the given description corresponds to an observational study or an experiment. In each case, give a brief explanation of your choice.Clinical Trial In a clinical trial of the cholesterol drug Lipitor, 188 subjects were given 20mg doses of the drug, and 3.7% of them experienced nausea (based on data from Pfizer, Inc.).

In Exercises 58, determine whether the given description corresponds to an observational study or an experiment. In each case, give a brief explanation of your choice.Touch Therapy Nineyearold Emily Rosa was an author of an article in the Journal of the American Medical Association after she tested professional touch therapists. Using a cardboard partition, she held her hand above one of the therapist's hands, and the therapist was asked to identify the hand that Emily chose.

In Exercises 58, determine whether the given description corresponds to an observational study or an experiment. In each case, give a brief explanation of your choice.Happiness Survey In a study sponsored by CocaCola, 12,500 people were asked what contributes most to their happiness, and 77% of the respondents said that it was their family or partner

In Exercises 920, identify which of these types of sampling is used: random, systematic, convenience, stratified, or cluster.Harry Potter The author collected sample data by randomly selecting 12 different pages from Harry Potter and the Sorcerer's Stone and then finding the number of words in each sentence on each of those pages.

In Exercises 920, identify which of these types of sampling is used: random, systematic, convenience, stratified, or cluster. Sexuality of Women The sexuality of women was discussed in Shere Hite's book Women and Love: A Cultural Revolution. Her conclusions were based on sample data that consisted of 4500 mailed responses from 100,000 questionnaires that were sent to women.

In Exercises 920, identify which of these types of sampling is used: random, systematic, convenience, stratified, or cluster.Twitter Poll In a Pew Research Center poll, 1007 adults were called after their telephone numbers were randomly generated by a computer, and 85% of the respondents were able to correctly identify what Twitter is

In Exercises 920, identify which of these types of sampling is used: random, systematic, convenience, stratified, or cluster. Ecology When collecting data from different sample locations in a lake, a researcher uses the line transect method by stretching a rope across the lake and collecting samples at every interval of 5 meters.

In Exercises 920, identify which of these types of sampling is used: random, systematic, convenience, stratified, or cluster.CBS News The CBS News station in New York City often obtains opinions by interviewing neighbors of a person who is the focus of a news story

In Exercises 920, identify which of these types of sampling is used: random, systematic, convenience, stratified, or cluster.Acupuncture Study In a study of treatments for back pain, 641 subjects were randomly assigned to the four different treatment groups of individualized acupuncture, standardized acupuncture, simulated acupuncture, and usual care (based on data from A Randomized Trial Comparing Acupuncture, Simulated Acupuncture, and Usual Care for Chronic Low Back Pain, by Cherkin et al., Archives of Internal Medicine, Vol. 169, No. 9).

In Exercises 920, identify which of these types of sampling is used: random, systematic, convenience, stratified, or cluster.Deforestation Rates Satellites are used to collect sample data used to estimate deforestation rates. The Forest Resources Assessment of the UN Food and Agriculture Organization uses a method of selecting a sample of a 10kmwide square at every 1 intersection of latitude and longitude.

In Exercises 920, identify which of these types of sampling is used: random, systematic, convenience, stratified, or cluster.Dictionary The author collected sample data by randomly selecting 20 different pages from a printed version of the MerriamWebster Dictionary and then counting the number of defined words on each of those pages.

In Exercises 920, identify which of these types of sampling is used: random, systematic, convenience, stratified, or cluster.Testing Lipitor In a clinical trial of the cholesterol drug Lipitor, subjects were partitioned into groups given a placebo or Lipitor doses of 10 mg, 20 mg, 40 mg, or 80 mg. The subjects were randomly assigned to the different treatment groups (based on data from Pfizer, Inc.).

In Exercises 920, identify which of these types of sampling is used: random, systematic, convenience, stratified, or cluster.Exit Polls On the day of the last presidential election, ABC News organized an exit poll in which specific polling stations were randomly selected and all voters were surveyed as they left the premises.

In Exercises 920, identify which of these types of sampling is used: random, systematic, convenience, stratified, or cluster.Literary Digest Poll In 1936, Literary Digest magazine mailed questionnaires to 10 million people and obtained 2,266,566 responses. The responses indicated that Alf Landon would win the presidential election, but Franklin D. Roosevelt actually won the election.

In Exercises 920, identify which of these types of sampling is used: random, systematic, convenience, stratified, or cluster.Highway Strength The New York State Department of Transportation evaluated the quality of the New York State Throughway by testing core samples collected at regular intervals of one mile. Simple Random Samples. In Exercises 2126, determine whether the sample is a simple random sample. Give a brief explanation of your choice

Bayer Aspirin Bayer HealthCare LLC produces lowdose aspirin pills designed to contain 81 mg of aspirin. Because each pill contains other ingredients, including corn starch, talc, and propylene glycol, it is difficult to check whether manufactured pills contain 81 mg of aspirin. A quality control plan is to select every 1000th pill, which is then tested for the correct amount of aspirin.

Market Research In order to test for a gender gap in the way that men and women purchase cars, the Grant Survey Company polls exactly 750 adult men and 750 adult women randomly selected from adults in the United States.

PostElection Survey In the last general election, 132,312 adults voted in Dutchess County, New York. You plan to conduct a postelection survey of 500 of those voters. After obtaining a list of those who voted, you number the list from 1 to 132,312, and then you use a computer to randomly generate 500 numbers between 1 and 132,312. Your sample consists of the voters corresponding to the selected numbers.

Jury Selection According to the State of New York Unified Court System, names of potential jurors are selected from a variety of different sources. When a trial requires a jury, names from the list are randomly selected in a way that is equivalent to writing the names on slips of paper, mixing them in a bowl, and selecting the required number of potential jurors.

Mall Research Mall managers commonly research how customers use the malls. The author was approached by a pollster at the Galleria Mall in Dutchess County, New York. The pollster was obviously selecting subjects who appeared to be approachable.

Car Crash Tests The National Highway Traffic Safety Administration (NHTSA) conducts crash tests of cars. One car of each different model is randomly selected for testing.

In Exercises 2730, indicate whether the observational study used is crosssectional, retrospective, or prospective.Nurses Health Study The Nurses Health Study was started in 1976 with 121,700 female registered nurses who were between the ages of 30 and 55. The subjects were surveyed in 1976 and every two years thereafter. The study is ongoing.

In Exercises 2730, indicate whether the observational study used is crosssectional, retrospective, or prospective.Drinking and Driving Study In order to study the seriousness of drinking and driving, a researcher obtains records from past car crashes. Drivers are partitioned into a group that had no alcohol consumption and another group that did have evidence of alcohol consumption at the time of the crash.

In Exercises 2730, indicate whether the observational study used is crosssectional, retrospective, or prospective.Smoking Study Researchers from the National Institutes of Health want to determine the current rates of smoking among adult males and adult females. They conduct a survey of 500 adults of each gender.

In Exercises 2730, indicate whether the observational study used is crosssectional, retrospective, or prospective.Meat and Mortality Researchers at the National Cancer Institute studied meat consumption and its relationship to mortality. Approximately onehalf million people were surveyed, and they were then followed for a period of 10 years

In Exercises 3134, identify which of these designs is most appropriate for the given experiment: completely randomized design, randomized block design, or matched pairs design.Lisinipril Lisinipril is a drug designed to lower blood pressure. In a clinical trial of Lisinipril, blood pressure levels of subjects are measured before and after they have been treated with the drug.

In Exercises 3134, identify which of these designs is most appropriate for the given experiment: completely randomized design, randomized block design, or matched pairs design.Aspirin A clinical trial of aspirin treatments is being planned to determine whether the rate of myocardial infarctions (heart attacks) is different for men and women.

In Exercises 3134, identify which of these designs is most appropriate for the given experiment: completely randomized design, randomized block design, or matched pairs design.West Nile Vaccine Currently, there is no approved vaccine for the prevention of West Nile virus. A clinical trial of a possible vaccine is being planned to include subjects treated with the vaccine while other subjects are given a placebo.

In Exercises 3134, identify which of these designs is most appropriate for the given experiment: completely randomized design, randomized block design, or matched pairs design.HIV Vaccine The HIV Trials Network is conducting a study to test the effectiveness of two different experimental HIV vaccines. Subjects will consist of 80 pairs of twins. For each pair of twins, one of the subjects will be treated with the DNA vaccine and the other twin will be treated with the adenoviral vector vaccine.

Blinding For the study described in Exercise 34, blinding will be used. What is blinding, and why was it important in this experiment?

Sample Design Literacy In Cardiovascular Effects of Intravenous Triiodothyronine in Patients Underdoing Coronary Artery Bypass Graft Surgery (Journal of the American Medical Association, Vol. 275, No. 9), the authors explain that patients were assigned to one of three groups: (1) a group treated with triidothyronine, (2) a group treated with normal saline bolus and dopamine, and (3) a placebo group given normal saline. The authors summarize the sample design as a prospective, randomized, doubleblind, placebocontrolled trial. Describe the meaning of each of those terms in the context of this study