Exam 4: Data Collection and Sampling

To give away a door prize, the hostess of a Tupperware party put each person's name into a hat, mixed them up, and selected one name. What sampling method was used?

A senator wants to estimate the mean age of registered voters in her state. Unfortunately, she does not have a complete list of households in her state. Describe a sampling plan that would be suitable for her purposes.

In a(n) ____________________ study, individuals are randomly assigned to different treatments and the results are compared.

Which of the following describes selection bias?

A(n) ____________________ sample is obtained by separating the population into groups and taking a simple random sample from each group.

A question on a survey that was not answered is an example of an open-ended question.

Briefly describe three types of nonsampling errors.

An experiment involves collecting data about persons or objects by deliberately exposing them to some kind of change and comparing the results.

The target population is the population about which we want to draw inferences and conclusions, while the sampled population is the actual population from which the sample has been taken.

Selection bias is a systematic tendency to favor including individuals with particular characteristics, while excluding individuals with other characteristics.

A pharmaceutical company interested in measuring how often physicians prescribe a certain drug has selected a simple random sample from each of two groups: M.D. (Medical Doctors) and D.O. (Osteopaths). What is this type of sampling called?

Discuss one advantage and one disadvantage of a self-administered survey as a method of data collection.

A sampling error can be reduced by taking a larger sample size.

Soft Drink: A soft drink manufacturer has been supplying its products in bottles to grocery stores and in cans to small convenience stores. The company is analyzing sales of this product to determine which type of packaging is preferred by customers. -Outline a better method for designing this study, so the same types of stores don't get the same types of packaging.

Selection bias occurs when researchers select biased questions to include on a survey.

A regular feature in many newspapers asks readers to respond via e-mail to a survey question. The percentages of yes and no responses are usually reported the following day. Should we ignore the results of these surveys? Explain.

Pollsters want to know what percentage of all registered voters in Missoula, Montana, intend to vote in the next election. They visit with 350 people at the downtown shopping mall during one afternoon and ask each person whether or not they intend to vote. Are the target population and the sampled population the same in this case? Explain.

List one advantage and one disadvantage of a telephone interview as a method of data collection.

Self-administered surveys usually have a high response rate.

In a self-administered survey, the individuals in the sample are typically contacted by ____________________.