Tuesday

July 28, 2015

July 28, 2015

Posted by **Lisa** on Monday, August 26, 2013 at 2:08pm.

Define the term sample?

A) A sample is a numeric characteristic of a sample

B) A sample is a numeric characteristic of a population

C) A sample is the entire collection of individuals about whom we would like to obtain information

D) A sample is a subset of the entire collection of individuals about whom we like to obtain information ( i chose this one)

2. Which of the following are reasons to use sampling?

I. Sampling saves time.

II. Sampling saves money.

III. Sampling is sometimes more precise than analyzing the whole population through a census.

A) I and II

B) I and III

C) II and III

D) All of above ( I chose this one)

3. Which is true about sampling?

I. An attempt to take a census will always result in less bias than using a sample.

II. Sampling error is usually reduced when the sample size is larger.

III. Sampling error is the result of random variations and is always present

A) all of above

B) I only

C) II and III

D) II only ( I chose this one)

E) III only

4. The Stanford-Binet IQ test is known to have a mean of 100 and a standard deviation of 15. A sample of 25 students was given the exam, and the mean for this group was 110.

Select the term which best describes the number 100.

A) population

B) sample

C) statistic ( i chose this one)

D) parameter

5)Mr. Smith works at a computer consultant company that provides technical information to computer departments of various manufacturing companies. Mr. Smith is alarmed at the number of spyware programs on the internet. He locates a study that states that 75% of all computers have been infected with a virus at some time in the past year. Mr. Smith wants to determine if his clients have experienced viruses on their computers at a comparable rate. He contacts a random sample of his clients and he finds that only 30% of his clients reported a computer infected with a virus.

What term best describes the figure of 30%?

A) Statistic

B) Parameter (i chose this one)

C) bias

D) sample

E) population

6)A local school district decides to randomly test high school students for attention deficit disorder (ADD). There are three high schools in the district, each with grades 9-12. There are a total of 1500 students in the three high schools. The school board pools all of the students together and randomly samples 250 students.

The percentage of high school students in the school district with ADD is known as:

A) census

B) the sampling method

C) the sample

D) the population parameter of interest ( i chose this one)

E) the sampling frame

7)The total number of students from question 6 represents what?

A) Voluntary sampling

B) the population (I chose this one)

C) the population parameter of interest

D) a census

E) the sample

8) A magazine publisher will mail a survey to 12% of its subscribers that will be chosen at random. The survey asks about the quality of its subscription service.

A listing of all of the subscribers, who have an equal and random chance to be chosen for this survey, represent what?

A) Census

B) the sampling method

C) the sampling frame ( i chose this one)

D) the sample

E) the population parameter of interest

9) Before premiering a blockbuster movie at a theater, test screenings are done beforehand. A small number of selected theaters are chosen geographically throughout the country. Each theater chosen is supposed to be representative of theatergoers throughout the country. Everyone is interviewed when the movie is over.

Identify the type of sampling used in this example

A) voluntary response

B) stratified

C) multistage

D) cluster ( I chose this one)

E) attempted census

10) A newly-premiered play just ended that evening at a local theater. Theater management briefly interviews every seventh person leaving the theater to see if that person will recommend the play at that theater to other people.

Identify the type of sampling used in this example

A) Cluster

B) voluntary response

C) convienience

D) systematic ( i chose this one)

E) stratified

11) A magazine publisher mails a survey to every subscriber asking about the quality of its subscription service.

Mailing a survey to every subscriber represents what type of sampling?

A) random

B) stratified

C) attempted census ( I chose this one)

D) cluster

E) systematic

12) 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?

A) Undercoverage of the population

B) Nonresponse bias ( i chose this one)

C) Voluntary response bias

D) Response bias

E) There does not seem to be any bias.

13) A referendum has been put forward in Christian County to enact a weekday curfew for teenagers. Radio station WTIM, a station that plays easy-listening music, is conducting a survey to determine what proportion of Christian County citizens support the referendum. Throughout the day the radio station airs announcements asking listeners to call in their opinion on the following question: "Should Christian County enact a weekday curfew for teenagers?" The goal of the survey is to identify if residents of Christian County feel support this proposal. Of course, people who are selected for the survey can elect to participate or not participate.

Identify how this survey design has undercoverage bias

A) Some listeners may refuse to participate, and those who refuse may differ on some characteristics from those who choose to respond. ( I chose this one)

B) The only people who can participate in the survey are the listeners of the station; non-listeners are excluded. The listeners may not be representative of the population of citizens of Christian County.

C) Some listeners will participate and some will not. Those who do participate tend to be those people who feel strongly about the issue.

- Statistics -
**PsyDAG**, Tuesday, August 27, 2013 at 2:52pm1. correct

2. Wrong. Look up definitions of 'sample" and "Census".

3. Wrong. Look up sampling error.

4. Wrong. Look up statistic and parameter.

5. Wrong. Look up statistic and parameter.

6. Right.

7. Right.

8. Right.

9. Right.

10. Right.

11. Right.

12. Wrong. What if you were asked this question? What would you say?

13. Wrong.

- Statistics -
**cat**, Monday, January 20, 2014 at 9:52pm1 a

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