Question 1

Before premiering a blockbuster movie at a theatre,test screenings are done beforehand.A small number of selected theatres are chosen geographically throughout the country.Each theatre chosen is supposed to be representative of theatregoers in that area.Everyone is interviewed when the movie is over.Identify the type of sampling used in this example.

Accepted Answer

Cluster sampling is used when the population is too large to sample from every individual, so clusters or groups are created and a representative sample is taken from each cluster. In this case, the selected theatres are clusters representing the theatregoers in that area, and a sample is taken from each cluster by interviewing everyone who saw the movie.

Question 2

A cereal manufacturer randomly samples households across the country by telephone.The survey asks the consumer to explain honestly in fifty words or less why he or she likes or dislikes its brand of cereals.It is also stated that for those who participate in this telephone survey,a random drawing will be held for an all-expense paid,two-week cruise.What,if any,will be the most noticeable bias for this survey?

Accepted Answer

The answer of A cereal manufacturer randomly samples households across...

Question 3

A mega-discount chain store just opened a new clothing store in town emphasizing mainly women's clothing.Before opening,management had to decide whether to only carry either men's,women's,boys',girls',or infants' clothing.After performing representative sampling of potential customers from each of these groups,it was decided to carry only women's clothing.Identify the type of sampling used in this example.

Accepted Answer

Stratified sampling involves dividing the population into strata (subgroups) and randomly selecting samples from each stratum. In this example, the population was divided into groups based on the type of clothing they would be interested in purchasing. A sample was then taken from each group to help management make a decision on what type of clothing to carry. Therefore, this is an example of stratified sampling.

Question 4

At the end of each semester a local university requires a professor's evaluation.An evaluation survey is given to each student to fill out.Identify the type of sampling used in this example.

Accepted Answer

This is attempted census because the evaluation survey is given to every student, and the goal is to evaluate every professor.

Question 5

Inside the boxes of a new brand of cereal,is a short survey that can be mailed back for free to the manufacturer.The survey asks the consumer if he or she likes the cereal or not.What,if any,will be the most noticeable bias for this survey?

Accepted Answer

The most noticeable bias for this survey is voluntary response bias, as the survey can only be completed and returned by consumers who choose to do so. This means that the responses may not be representative of the overall population and may be skewed towards those who have a strong opinion (either positive or negative) about the cereal.

Question 6

A newspaper conducted a random telephone survey during the day regarding the percentage of stay-at-home moms and dads in the typical household.What,if any,will be the most noticeable bias for this survey?

Accepted Answer

The answer of A newspaper conducted a random telephone survey...

Question 7

During the winter season,a prominent newspaper reporter is interested in writing a story about the lack of proper heating of apartment buildings in the city in which he lives.During a particular frigid weekend,this reporter manages to interview almost everyone in his own apartment building.The reporter finds that everyone,including himself,is satisfied with the heating in the apartment building.Identify the type of sampling used in this example.

Accepted Answer

Convenience sampling was used because the reporter only interviewed people from his own apartment building, which was a convenient sample for him to access. It is not a representative sample of the entire city, so cluster sampling, systematic sampling, and attempted census are not applicable. Voluntary response sampling would involve people choosing to participate in the survey, but the reporter actively sought out and interviewed everyone in his apartment building.

Question 8

A newly-premiered play just ended that evening at a local theatre.Theatre management briefly interviews every eighth person leaving the theatre to see if that person will recommend the play at that theatre to other people.Identify the type of sampling used in this example.

Accepted Answer

Systematic sampling is used here, as every eighth person leaving the theatre is selected for the interview, following a specific system or pattern.

Question 9

A newspaper reporter randomly sampled households by telephone during various times of the day.The people sampled are within the area of the newspaper's distribution.The newspaper reporter asked,"Are you patriotic in a time of war or armed conflict?" What,if any,will be the most noticeable bias for this survey?

Accepted Answer

The most noticeable bias for this survey would be response bias. The question asked may invoke a social desirability bias, where respondents may feel pressured to answer in a way that is socially acceptable, rather than their true feelings. Additionally, the question may be interpreted differently by different respondents, leading to inaccuracies in the results.

Question 10

At a small college there are 120 freshmen,90 sophomores,110 juniors,and 80 seniors.A school administrator selects a random sample of 12 of the freshmen,a random sample of 9 of the sophomores,a random sample of 11 of the juniors,and a random sample of 8 of the seniors.She then interviews all the students selected.Identify the type of sampling used in this example.

Accepted Answer

The administrator used proportional stratified sampling by selecting a random sample from each stratum based on the proportion of freshmen, sophomores, juniors, and seniors in the entire college. This allows for each group to be represented in the sample and ensures that the sample is representative of the entire college population.

Question 11

A popular soft drink company periodically sets up survey booths in various malls and grocery stores that are chosen at random.The employees working the booths ask interested individuals to fill out a very short survey on the quality of the company's drinks.While filling out the surveys,the individuals are told that a properly completed survey will be rewarded with giveaways,such as free samples,T-shirts,generous coupons,and possibly an appearance in a new television commercial.What,if any,will be the most noticeable bias?

Accepted Answer

The most noticeable bias in this scenario is response bias. The promise of rewards and giveaways can influence individuals to give positive feedback and rate the quality of the drinks higher than they would have without the incentives. This can lead to an overestimation of the actual quality of the drinks.

Question 12

A popular soft drink company distributes written surveys with its product that a customer can fill out and mailed in or the survey can be filled out electronically on the internet.What,if any,will be the most noticeable bias?

Accepted Answer

The most noticeable bias in this case would be voluntary response bias, as the only people who fill out the survey are those who choose to do so. This could lead to an overrepresentation of certain types of customers who are more likely to respond to the survey, and therefore may not be an accurate representation of the entire customer base.

Question 13

Management at a particular post office wants to know about the quality of its face-to-face service at its customer service windows.For one week,the post office will ask the customers directly.After a customer is helped,a different employee asks the customer a short question about his or her customer service experience.The customer's comments are then transcribed by a secretary.This survey runs smoothly and a lot of customer comments are collected.What,if any,is the most noticeable bias for this survey regarding customer service at this post office for that week?

Accepted Answer

The answer of Management at a particular post office wants...

Question 14

A newspaper reporter decided to sample residents of all major metropolitan areas in the entire country.This sampling asked if the residents liked living in their city,or are they considering moving,and if so,where? Unfortunately,this survey went over budget and was stopped,and only the east coast of the country was adequately interviewed.With regards to having this survey labeled as representing the entire country,what,if any,will be the most noticeable bias for this survey as it is now?

Accepted Answer

The survey suffers from undercoverage bias as only residents from the east coast of the country were interviewed, which does not represent the entire country.

Question 15

At the local university a survey was being done on whether or not the students liked the cafeteria food.The survey was located in the college newspaper and was to be filled out and sent to the editing office.Identify the type of sampling used in this example.

Accepted Answer

This is an example of voluntary response sampling, as the survey was made available to anyone who chose to fill it out and send it in. It does not involve randomly selecting participants or dividing the population into specific groups (stratified sampling). There is also no attempt to contact every single student (attempted census) or to select a specific pattern or interval (systematic sampling).

Question 16

One day a popular morning show on a local radio station conducted a phone-in survey regarding the recent rise in the city's various utility rates.The survey lasted the entire morning show.Other than time constraints of the show,no callers were knowingly refused to voice their opinion on-air.The transcribed results were sent to various governmental agencies and local politicians.Identify the type of sampling used.

Accepted Answer

Voluntary response sampling is used here because individuals chose to participate by calling into the show, indicating their willingness to voice their opinions without any selection criteria applied by the survey conductors.

Question 17

A non-for-profit consumer agency wanted to investigate the economic and humanitarian contribution of this country's pharmaceutical companies by sampling large companies and businesses of all types.It was decided to sample the pharmaceutical companies first.After surveying the pharmaceutical companies,someone at the consumer agency wanted to distribute the data early.What,if any,will be the most noticeable bias in distributing the survey at this point in time?

Accepted Answer

The most noticeable bias would be undercoverage of the population because only pharmaceutical companies have been surveyed at this point, and businesses of all other types have not yet been included in the survey. This means the sample does not fully represent the entire population of interest, which includes businesses of all types, not just pharmaceutical companies.

Question 18

Management at a post office is curious about its services in one small town.Every address within that town,including business and residential,is mailed a survey inquiring about the post office's quality of service.The post office does receive a respectable 25% response rate to the survey.However,what,if any,is the most noticeable bias for this survey?

Accepted Answer

The answer of Management at a post office is curious...

Question 19

A blockbuster movie had just premiered on exactly 1,257 screens throughout the country.Within the first week,a few theatres were chosen at random,and then theater management interviewed approximately 5% of the theatregoers at those selected theatres.All these theatregoers loved the movie,therefore management decided to increase the number of showings per week.Identify the type of sampling used in this example.

Accepted Answer

The answer of A blockbuster movie had just premiered on...

Question 20

An education researcher randomly selects 38 schools from one school district and interviews all the teachers at each of the 38 schools.Identify the type of sampling used in this example.

Accepted Answer

This is an example of cluster sampling because the schools are being randomly selected as clusters and then all the teachers within each school are being sampled.

Quiz 11: Sample Surveys