Exam 8: Qualitative and Quantitative Sampling

Professor Howlick's questionnaire asked each student to name every other student with whom they had drank with during the past two months. Kerry Sobiski, his assistant, sent emails for the online survey to each person named by students in the first sample. The same question was asked in this online survey. Ms. Sobiski next sent emails for the online survey to everyone named as a drinking partner in the second sample and so on until she had emailed ten different waves of online surveys. She then drew up a list of all students who drank with anyone else who answered the online survey, and used it as a sample for a study on drinking networks on campus. What kind of sampling was Ms. Sobiski using?

Refer to the following paragraph to answer the questions below. Robert Warner, president of a local TV station, recently conducted a study of TV viewers in his area. He obtained a list of all residential customers from the cable TV company billing list. Oddly enough, he put every customer name on a 3x5 note card, and mixed them up in one raffle barrel. He then choose 1000 note cards out of a possible 20,000 customer cards). A trained interviewer visited each household and asked detailed questions about the viewing habits of various family members. -How large is his sampling ratio?

A nonrandom sample that involves dividing a sampling frame into various categories and selecting a predetermined number of respondents from each category is called a

Often researchers want to sample a network of people or organizations. What sampling techniques would be best? Why is this technique useful for this type of research?

Refer to the following paragraph to answer the questions below. Robert Warner, president of a local TV station, recently conducted a study of TV viewers in his area. He obtained a list of all residential customers from the cable TV company billing list. Oddly enough, he put every customer name on a 3x5 note card, and mixed them up in one raffle barrel. He then choose 1000 note cards out of a possible 20,000 customer cards). A trained interviewer visited each household and asked detailed questions about the viewing habits of various family members. -What is the sampling frame of the study?

What type of sampling did Professor Howlick use?

Professor Hangnail wants to study how people join a small extremist political organization dedicated to right- wing ideas. He first interviews recent recruits and asks who introduced him/her to the organization. He next interviews the named person and asks who introduced them to the organization, and so forth. What type of sample is the professor using?

Refer to the following paragraph to answer the questions below. Dr. Martinez draws a systematic random sample of 350 churches from all churches and religious institutions in the 3 Pacific coast states of the continental U.S. His sampling frame has 35,000 institutions. -What is the sampling interval?

Explain the difference between a systematic random sample and a stratified random sample. When would a research use each sampling technique?

Outline the differences between the three nonprobability sampling techniques: haphazard, sequential, and theoretical.

Refer to the following paragraph to answer the questions below. The Young Children's Charity would like to provide an accurate estimate of how much it costs to raise a child between the ages of 2 and 12 for its fund raising campaign. They contracted with you to find out how much households spent on raising a child in 1996. They gave you a list all 400,000 residential telephone customers in the area they will operate the campaign. You sampled every 400th address on the list. The Charity will have a survey company contact each household sampled and ask whether or not there is a child between 2 and 12 years of age living in the household. If there is, they will ask other questions and record the total amount spent raising a child during 1996. -What is a range of values, usually a little higher and lower than a specific value found in a sample, within which a researcher has a specified and high degree of confidence that the population parameter lies?

Refer to the following paragraph to answer the questions below. Robert Warner, president of a local TV station, recently conducted a study of TV viewers in his area. He obtained a list of all residential customers from the cable TV company billing list. Oddly enough, he put every customer name on a 3x5 note card, and mixed them up in one raffle barrel. He then choose 1000 note cards out of a possible 20,000 customer cards). A trained interviewer visited each household and asked detailed questions about the viewing habits of various family members. -What type of sampling did he use?

When is random-digit dialing RDD) used? What is the population in RDD? Does RDD avoid sampling frame issues?

A researcher asks students in an introductory sociology class to take an Internet survey on student attitudes towards puppy dogs. What kind of sample is the researcher using?

Refer to the following paragraph to answer the questions below. Professor Howlick is studying incoming freshmen) student drinking behavior at Boozemen State University in Boozemen, Kansas. Every incoming freshman is required to have a university email address. After obtaining a list of all incoming freshmen students email addresses, he numbered every email address from 1 to 4,000. Using a random-number table, he obtained a sample of 200 freshman email addresses. He then emailed students requesting them to take an online survey. He also had two follow-up email reminders. A total of 180 students took the online survey. -What is Howlick's sampling frame?

Refer to the following paragraph to answer the questions below. Professor Howlick is studying incoming freshmen) student drinking behavior at Boozemen State University in Boozemen, Kansas. Every incoming freshman is required to have a university email address. After obtaining a list of all incoming freshmen students email addresses, he numbered every email address from 1 to 4,000. Using a random-number table, he obtained a sample of 200 freshman email addresses. He then emailed students requesting them to take an online survey. He also had two follow-up email reminders. A total of 180 students took the online survey. -What is the population?

Refer to the following paragraph to answer the questions below. The Young Children's Charity would like to provide an accurate estimate of how much it costs to raise a child between the ages of 2 and 12 for its fund raising campaign. They contracted with you to find out how much households spent on raising a child in 1996. They gave you a list all 400,000 residential telephone customers in the area they will operate the campaign. You sampled every 400th address on the list. The Charity will have a survey company contact each household sampled and ask whether or not there is a child between 2 and 12 years of age living in the household. If there is, they will ask other questions and record the total amount spent raising a child during 1996. -What type of sample will you be using?

It is easy to suggest that a bigger sample is more representative of a population than a smaller sample. Is this always true? Explain when a larger sample in itself is not always the best.

Dr. Simpson wants to investigate opinions favoring/opposing federalized healthcare among adults living in cities ranging from 100,000 and 250,000 people. First, Dr. Simpson randomly selects 10 cities in the U.S. that have a population between 100,000 and 250,000. Second, he randomly selects 10 census tracts from each of the 10 cities a total of 100 census tracts). Third, Dr. Simpson selects two blocks from each census tract a total of 200 blocks). Fourth, he randomly selects 5 houses from each block a total of 1000 households). What kind of sample is Dr. Simpson using?

How do researchers decide how large of a sample to use? What are some of the issues that influence this decision?