Statistics Chapter 10: Sample Surveys – Flashcards

You are trying to study the amount of financial aid students at your University receive. You sample 50 students and find out the average size of their financial aid packages. The average of your sample is a​ __________.

You are doing a study for a​ non-profit group helping​ at-risk children in your city. Suppose you know that​ 14.2% of the children in your city live in poverty. This percentage is an example of a ​ __________.

If you create an online​ survey, individuals can choose on their own whether to participate in the sample. This causes a form of bias called​ __________.

When you sample so that every combination of individuals in your population has an equal chance of being chosen you are taking a​ __________.

A friend of yours in your intro stats class obtains permission to randomly sample the University student body to conduct a satisfaction survey on some recent changes to the enrollment process. She randomly samples 50​ freshmen, 50​ sophomores, 50​ juniors, and 50 seniors. This is an example of a​ __________ sample.

Some friends of yours in a political science class are angry about a new town ordinance restricting​ off-campus parties. They make an online survey asking​ students' opinions. This type of sampling might be classified as a​ __________ sample.

At its​ website, a polling company publishes results of a new survey each day. Scroll down to the end of the published results and​ you'll find a statement that includes words as shown below. Results are based on telephone interviews with​ 1,008 national​ adults, aged 18 and​ older, conducted on April​ 2-5, 2007 ... In addition to sampling​ error, question wording and practical difficulties in conducting surveys can introduce error or bias into the findings of public opinion polls. a. Identify the population of interest. b. What is the sampling​ frame? c. What​ problems, if​ any, would you be concerned about in matching the sampling frame with the​ population?

Researchers want to estimate the percentage of people who thought drinking and driving was a serious problem. Researchers waited outside a bar to question people. They usually find 17 % of bar patrons believe drinking and driving is a serious problem. a. Identify the Population b. Identify the population parameter of interest c. Identify the sampling frame d. Identify the sample e.Identify the sampling method f. Identify who was left out of the study g. Identify any potential sources of bias

General Motors wants to administer a satisfaction survey to its current customers. Using their customer​ database, the company randomly selects 60 customers and asks them about their level of satisfaction with the company. What type of sampling is​ used?

To determine her power usage​, Jean divides up her day into three​ parts: morning,​ afternoon, and evening. She then measures her power usage at 2 randomly selected times during each part of the day. What type of sampling is​ used?

To estimate the percentage of defects in a recent manufacturing​ batch, a quality control manager at Ford selects every 12th truck that comes off the assembly line starting with the fourth until she obtains a sample of 140 trucks. Which type of sampling is​ used?

To determine customer opinion of their safety safety features​, Toyota randomly selects 130 dealerships during a certain week and surveys all customers visiting the dealership. Which type of sampling is​ used?

A group of people are classified according to music preference and then random samples of people from each group are taken. Choose the correct sampling technique below.

A state is divided into regions using area codes. A random sample of 25 area code areas is selected. Choose the correct sampling technique below.

The first 20 students leaving the cafeteria are asked how much money they spent on textbooks for the semester.

Golf balls in a basket are shaken and then balls are selected from the basket.

At its​ website, a polling company publishes results of a new survey each day. Scroll down to the end of the published results and​ you'll find a statement that includes words as shown below. Results are based on telephone interviews with​ 1,008 national​ adults, aged 18 and​ older, conducted on April​ 2-5, 2007 ... In addition to sampling​ error, question wording and practical difficulties in conducting surveys can introduce error or bias into the findings of public opinion polls. a. For this​ survey, identify the population of interest. b.The company performs its surveys by phoning numbers generated at random by a computer program. What is the sampling​ frame? c.What​ problems, if​ any, would you be concerned about in matching the sampling frame with the​ population?

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 as soon as they exit the park. a. What kind of sample is​ this? b. What is the sampling​ frame? c. Is the sample likely to be representative of the population of​ interest? d. What members of the population of interest are​ omitted?

Administrators at a university were interested in estimating the percentage of students who are the first in their family to go to college. The university student body has about 47,000 members. a. Select several dormitories at random and contact everyone living in the selected dorms. b. Using a​ computer-based list of registered​ students, contact 100 ​freshmen, 100 ​sophomores, 100 ​juniors, and 100 seniors selected at random from each class. c. Using a​ computer-based alphabetical list of registered​ students, select one of the first 30 names on the list at​ random, and then contact the student whose name is 60 names​ later, and then every 60th name after that.

What problems do you see with asking the following question of​ students? "Are you the first member of your family to seek higher​ education?"

Administrators at a university were interested in estimating the percentage of students who are the first in their family to go to college. The university student body has about 52,000 members. The university administration is considering a variety of ways to sample students for a survey. For each of these proposed survey​ designs, identify the problem. a. Publish an advertisement inviting students to visit a website and answer questions. b. Set up a table in the student union and ask students to stop and answer a survey.

In a large city school system with 26 elementary​ schools, the school board is considering the adoption of a new policy that would require elementary students to pass a test in order to be promoted to the next grade. The PTA wants to find out whether parents agree with this plan. Listed below are some of the ideas proposed for gathering data. For​ each, indicate what kind of sampling strategy is involved and what​ (if any) biases might result. Assume the schools are homogeneous and differ from each other. A. Randomly select one of the elementary schools and contact the parents of every student a. What kind of bias is most likely to result. B. Randomly select 10 parents from each elementary school. Send them a survey, and follow up with a home visit if they do not return the survey within a week. b. What kind of bias is likely to result? C. Randomly select 250 parents and send them a survey, follow up with a home visit if they do not return the survey within a week. c. What kind of bias is likely to result? D. Ask the parents for their opinions at the next PTA meeting. d. What kind of bias is likely to result?

A chemistry professor who teaches a large lecture class surveys his students who attend his class about how he can make the class more​ interesting, hoping he can get more students to attend. What does this survey method suffer​ from?

Which of the following statements about bias are​ true? I. Bias results from random variation and will always be present. II. Bias results from a sampling method likely to produce samples that do not represent the population. III. Bias is usually reduced when sample size is larger.

Two members of the PTA committee have proposed the accompanying questions to ask in seeking​ parent's opinions. Question 1 is​ "Should elementary​ school-age children have to pass​ high-stakes tests in order to remain with their​ classmates?" and Question 2 is​ "Should schools and students be held accountable for meeting yearly learning goals by testing students before they advance to the next​ grade?" Complete parts a and b below.