An amusement park has opened a new roller coaster. It is so popular that people are waiting for up to 3 hours for a 2-minute ride. Concerned about how patrons (who paid a large amount to enter the park and ride on the rides) feel about this, they survey every 10th person on the line for the roller coaster, starting from a randomly selected individual. Is it likely to be representative?

People generally don't think "health" when they hear the word "maggot," but one experiment tested the ability of maggots to remove dead tissue from open wounds that would not heal on their own. Sterile maggots were placed in a small pouch which, in turn, was placed on the wound. 100 men with wounds on their lower limbs were randomly assigned to receive either a traditional surgical treatment or maggot therapy. After eight days, the percentage of dead tissue in the wounds that underwent maggot treatment was 54.5%, compared to 66.5% with the surgical treatment. (The difference decreased with time, and the advantage disappeared by about day 15.) Neither patients nor the doctors evaluating the wounds knew which therapy had been applied. (Patients were blindfolded as bandages were changed.) Surprisingly, the number of patients that reported a crawling sensation in their wound was about the same in both groups! Identify the treatment and response variables.

Find the sum.

$$\sum _ { i = 1 } ^ { 20 } ( 2 i - 3 )$$

For the report about statistical studies, identify the sampling frame (if possible). If you can't tell, then say so-this often happens when we read about a survey. Hoping to learn what issues may resonate with voters in the coming election, the campaign director for a mayoral candidate randomly selects two blocks from each of the city's election districts. Staff members go there and interview all the residents they can find. The residents were asked to select the three most important issues from a prepared list.

An amusement park has opened a new roller coaster. It is so popular that people are waiting for up to 3 hours for a 2-minute ride. Concerned about how patrons (who paid a large amount to enter the park and ride on the rides) feel about this, they survey every 10th person on the line for the roller coaster, starting from a randomly selected individual. What is the sampling frame?

For the report about statistical studies, identify if any potential sources of bias you can detect and any problems you see in generalizing to the population of interest (if possible). If you can't tell, then say so-this often happens when we read about a survey. Hoping to learn what issues may resonate with voters in the coming election, the campaign director for a mayoral candidate randomly selects two blocks from each of the city's election districts. Staff members go there and interview all the residents they can find. The residents were asked to select the three most important issues from a prepared list.

An amusement park has opened a new roller coaster. It is so popular that people are waiting for up to 3 hours for a 2-minute ride. Concerned about how patrons (who paid a large amount to enter the park and ride on the rides) feel about this, they survey every person in line for the roller coaster, starting from a randomly selected individual.

What is the sampling frame?

An amusement park has opened a new roller coaster. It is so popular that people are waiting for up to 3 hours for a 2-minute ride. Concerned about how patrons (who paid a large amount to enter the park and ride on the rides) feel about this, they survey every 10th person on the line for the roller coaster, starting from a randomly selected individual. a) What kind of sample is this? b) What is the sampling frame? c) Is it likely to be representative? d) What members of the population of interest are omitted?

An amusement park has opened a new roller coaster. It is so popular that people are waiting for up to 3 hours for a 2-minute ride. Concerned about how patrons (who paid a large amount to enter the park and ride on the rides) feel about this, they survey every person in line for the roller coaster, starting from a randomly selected individual.

Is it likely to be representative?

For the report about statistical studies, identify the sample (if possible). If you can't tell, then say so-this often happens when we read about a survey. Hoping to learn what issues may resonate with voters in the coming election, the campaign director for a mayoral candidate randomly selects two blocks from each of the city's election districts. Staff members go there and interview all the residents they can find. The residents were asked to select the three most important issues from a prepared list.

An amusement park has opened a new roller coaster. It is so popular that people wait up to three hours for a two-minute ride. Concerned about how patrons (who paid a considerable amount to enter the park and ride on the rides) feel, they survey every tenth person in line for the roller coaster, starting from a randomly selected individual.

b) Is it possible to be representative?

The U.S. Fish and Wildlife Service plans to examine the fishing industry around Saginaw Bay. To do that, they choose five fishing boats at the end of a randomly chosen fishing day and count the numbers and types of all the fish on those boats.

a) What kind of design have they used?

Major League Baseball tests players to see whether they are using performance-enhancing drugs. Officials select a team at random, and a drug-testing crew show up unannounced to test all 40 players on the team. Each testing day can be considered a study of drug use in Major League Baseball. a) What kind of sample is this? b) Is that choice appropriate?

The U.S. Fish and Wildlife Service plans to examine the fishing industry around Saginaw Bay. To do that, they choose five fishing boats at the end of a randomly chosen fishing day and count the numbers and types of all the fish on those boats.

b) What could go wrong with the design that they have suggested?