Treatment of breast cancer is a controversial issue with treatment varying from radical mastectomy to radiation and chemotherapy combined with simple lumpectomy. One long-term study involved noting survival times of all breast cancer patients from over 100 hospitals and comparing the percentage of women still alive 5 years after radical mastectomies with the percentage of women still alive 5 years after radiation and chemotherapy combined with simple lumpectomy. The results seems to show a better outcome for women who received lumpectomy treatment. Which of the following statements are appropriate?

Treatment of breast cancer is a controversial issue with treatment varying from radical mastectomy to radiation and chemotherapy combined with simple...

A drug company wishes to test a new drug. A researcher assembles a group of volunteers and randomly assigns them to one of two groups -- one to take the drug and one to take a placebo. In addition, the company wants the experiment to be double-blinded. What is the meaning of double-blind in this situation?

A drug company wishes to test a new drug. A researcher assembles a group of volunteers and randomly assigns them to one of two groups -- one to take the...

A researcher is testing the effect of a new fertilizer on crop growth. He marks 30 plots in a field, splits the plots in half, and randomly assigns the new fertilizer to one half of the plot and the old fertilizer to the other half. After 4 weeks, he measures the crop yield and compares the effects of the two fertilizers. This design is an example of

A researcher is testing the effect of a new fertilizer on crop growth. He marks 30 plots in a field, splits the plots in half, and randomly assigns the...

In a recent poll of 1,500 randomly selected eligible voters, only 525 (35%) said they did not vote in the last election. However, a vote count showed that 80% of eligible voters actually did not vote in the last election. Which of the following types of bias is most likely to have occurred in the poll?

In a recent poll of 1,500 randomly selected eligible voters, only 525 (35%) said they did not vote in the last election. However, a vote count showed...

A television news editor would like to know how local registered voters respond to the question: "Are you in favor of the school bond measure that will be voted on in an upcoming special election?" A television survey is conducted during a break in the evening news by listing two telephone numbers side by side on the screen, one for viewer to call if they approve of the bond measure, and the other to call if they disapprove. This survey method could produce biased results for a number of reasons. Which of the following is the most obvious reason?

A television news editor would like to know how local registered voters respond to the question: "Are you in favor of the school bond measure that will...

A 2008 ballot initiative in California sought a constitutional ban on same sex marriage. Suppose a survey prior to the election asked the question, "Do you favor a law that would eliminate the right of same sex couples to marry?" This question could produce biased results. Which of the following is the most likely reason?

A 2008 ballot initiative in California sought a constitutional ban on same sex marriage. Suppose a survey prior to the election asked the question, "Do...

A nutritional consulting company is trying to find what percentage of the population of a town is overweight. The marketing department contact by telephone 600 people from a list of the entire town's population. About 100 people give answers to the survey. Which of the following is the most significant source of bias in this survey?

A nutritional consulting company is trying to find what percentage of the population of a town is overweight. The marketing department contact by telephone...

An experiment to measure the effect of giving hormones to girls affected by Turner's Syndrome was carried out recently in Vancouver. All 34 girls in the study were given the growth hormone and their heights were measured at the time the hormone was given and again one year later. No measurements were made on their final adult heights. Which of the following is not a problem with this experiment:

An experiment to measure the effect of giving hormones to girls affected by Turner's Syndrome was carried out recently in Vancouver. All 34 girls in the...

Since many individuals walk around their homes in their socks, a manufacturer has created a material for socks that is believed to be more resistant to wear than cotton. The manufacturer wishes to test this belief over a period of a month. Given a group of volunteers, which of the following designs will best test this new material's resistance to wear?

Since many individuals walk around their homes in their socks, a manufacturer has created a material for socks that is believed to be more resistant to...

For a certain experiment you have 8 subjects, of which 4 are female and 4 are male. The names are Males: Atwater, Bacon, Chu, Diaz Females: Johnson, King, Liu, Moore. There are two treatments, A and B. If a randomized block design is used, with the subjects blocked by their gender, which of the following is NOT a possible group of subjects who receive treatment A?

For a certain experiment you have 8 subjects, of which 4 are female and 4 are male. The names are Males: Atwater, Bacon, Chu, Diaz Females: Johnson, King,...

40% of the staff in a local school district have a master's degree. One of the schools in the district has only 4 teachers out of 15 with a master's degree. You are asked to design a simulation to determine the probability of getting this few teachers in a group this size. Which of the following assignments of the digits 0 through 9 would be appropriate for modeling this situation.

40% of the staff in a local school district have a master's degree. One of the schools in the district has only 4 teachers out of 15 with a master's degree....

A manufacturer wants to test a sample of the products his company produces. Products are produced in sets of 100, and each set of 100 is called a lot. The company produces hundreds of lots each day. The manufacturer decides to randomly select five lots from each day's production run and test every product in these five lots. Which of the following best describes this type of sampling?

A manufacturer wants to test a sample of the products his company produces. Products are produced in sets of 100, and each set of 100 is called a lot....

To test the effect of music on productivity, a group of assembly line workers are given portable mp3 players to play whatever music they choose while working for one month. For another month, they work without music. The order of the two treatments for each worker is determined randomly. This is

To test the effect of music on productivity, a group of assembly line workers are given portable mp3 players to play whatever music they choose while...

A study randomly assigned patients to treatment groups to determine the effect of taking aspirin in preventing the development of colon polyps. One group took an aspirin daily and the other group took a placebo. Neither the patients nor the doctors knew who was getting which pill. This study is best described as a

A study randomly assigned patients to treatment groups to determine the effect of taking aspirin in preventing the development of colon polyps. One group...

The editor of the newspaper at a large university wants to measure student opinion on a proposed change in graduation requirements. The editor randomly selects 100 freshman, 100 sophomores, 100 juniors and 100 seniors to take a short survey. This plan is an example of what kind of sampling?

The editor of the newspaper at a large university wants to measure student opinion on a proposed change in graduation requirements. The editor randomly...

A US government researcher wants to select a sample of tax returns that will include returns from a variety of different income levels. He divides the set of all the different incomes shown on the forms into 10 non-overlapping ranges. Then he randomly selects 100 tax returns from each. Which of the following best describes the sampling scheme used in this example?

A US government researcher wants to select a sample of tax returns that will include returns from a variety of different income levels. He divides the...

A company with offices in 5 different countries is interested in estimating the proportion of its employees in favor of banning smoking on the office premises. It is known that the views of people from different countries on issues like smoking tend to vary due to the influence of different local social structures. Which of the following is an appropriate sampling technique to use in this situation, and why?

A company with offices in 5 different countries is interested in estimating the proportion of its employees in favor of banning smoking on the office...

A civil engineer is testing the reliability of traffic signal controllers produced by two different companies. He has 20 sets of controllers from each company, and he has been given clearance to install them at 40 different intersections in the city. He randomly assigns the controllers from company A to 20 intersections and the controllers from company B to the other intersections. The most important reason for this random assignment is that

A civil engineer is testing the reliability of traffic signal controllers produced by two different companies. He has 20 sets of controllers from each...

An experimenter believes that two new exercise programs are more effective than any current exercise routines and wishes to compare the effectiveness of these two new exercise programs on physical fitness. The experimenter is trying to determine whether or not a control group which follows neither of these new programs but continues with current exercise routines would be beneficial. Which of the following can be said about the addition of a control group?

An experimenter believes that two new exercise programs are more effective than any current exercise routines and wishes to compare the effectiveness...

A test run to compare two statistics textbooks, one with a traditional approach and one with a new approach. A state university agrees to use the traditional text in all of its 30 classes, each with approximately 50 students. A private liberal art college agrees to use the new approach text in its 4 statistics classes, each with 20 students. A SRS of 30 statistics students at each school will take a standardized final exam, and the mean scores of the two groups will be compared. Is this a good experimental design?

A test run to compare two statistics textbooks, one with a traditional approach and one with a new approach. A state university agrees to use the traditional...

The owner of a factory that employs half the citizens in a small town is trying to decide whether to take a public stand on a controversial issue. He realizes that he would benefit from knowing how the townspeople feel. He randomly selects 50 of the townspeople from a list of all the town's population. He personally contacts all 50 and asks them their opinion on the issue. Most give him an answer, but 12 townspeople decline to participate. He decides to summarize his results based on the 38 responses. Which of the following list the most significant sources of bias in this survey?

The owner of a factory that employs half the citizens in a small town is trying to decide whether to take a public stand on a controversial issue. He...

A recent survey by a large-circulation Canadian magazine on the contribution of universities to the economy was circulated to 394 people who the magazine decided "are the most likely to know how important universities are to the Canadian economy." The main problem with using these results to draw conclusions about the general public's perception is

A recent survey by a large-circulation Canadian magazine on the contribution of universities to the economy was circulated to 394 people who the magazine...

A researcher is testing a company's new stain remover. He has contracted with 40 families who have agreed to test the product. He randomly assigns 20 families to the group that will use the new stain remover and 20 to the group that will use the company's current product. The most important reason for this random assignment is

A researcher is testing a company's new stain remover. He has contracted with 40 families who have agreed to test the product. He randomly assigns 20...

The coefficient of correlation

The coefficient of correlationa.) is the same as the coefficient of determinationb.) can be larger than 1c.) cannot be larger than 1d.) cannot be neg...

The symbol sigma2 is used to represent

The symbol sigma2 is used to representa.) the variance of the populationb.) the standard deviation of the samplec.) the standard deviation of the populationd.)...

The symbol sigma is used to represent

The symbol sigma is used to representa.) the variance of the populationb.) the standard deviation of the samplec.) the standard deviation of the populationd.)...

The variance can never be

The variance can never bea.) zerob.) larger than the standard deviationc.) negatived.) smaller than the standard deviationAnswer:&nbs...

The sample variance

The sample variancea.) is always smaller than the true value of the population varianceb.) is always larger than the true value of the population variancec.)...

The interquartile range is

The interquartile range isa.) the 50th percentileb.) another name for the variancec.) the difference between the largest and smallest valuesd.) the difference...

The first quartile

The first quartilea.) contains at least one third of the data elementsb.) is the same as the 25th percentilec.) is the same as the 50th percentiled.)...

The median is a measure of

The median is a measure ofa.) relative dispersionb.) absolute dispersionc.) central locationd.) relative locationAnswer:&nbs...

µ is an example of a

µ is an example of aa.) population parameterb.) sample statisticc.) population varianced.) modeAnswer:&nbs...