Exam 12: Determining How to Select the Sample

Calculation of the "skip interval" is important in which sampling plan?

Which of the following is NOT a method of substitution?

If we define our population as all households in the city of Chicago, Illinois, and we use the Chicago telephone directory from which to draw our sample units, we would likely have:

Tom and Mary Nesbitt commissioned a local university to determine if there would be adequate demand for sails on a large catamaran at a local beach frequented by vacationers. The beach was about 5 miles in length and was lined with hotels and condominiums that rented rooms and condos to thousands of visitors each year. At present, there were few water sports available and were limited to "active participant" rides, such as parasailing or kite sailing. The Nesbitts felt that if there was adequate demand, they may invest the required $750,000 needed to purchase the 110-foot-long catamaran that could carry as many as 80 passengers and a crew of eight on each trip. The Nesbitts felt that few of the persons living in the adjoining city near the beach would be in their target market. Instead, they felt 95% of their business would come from persons at the beach who would see the catamaran sailing back and forth and would walk to one of two locations to take the ride. "We want a sample taken of persons who are actually on the beach during a single weekday in June," Mary said. Given that you want to have a probability sample, which of the following sample methods would likely be most appropriate?

The blind draw method, or using a table of random numbers, is most appropriate for quota samples.

If a population were not distributed symmetrically, you would use:

In practice, simple random sampling should be strongly considered:

Simple random sampling is not a wise choice when you have:

Marketing researchers make use of samples because obtaining information from every single person in a market is impractical.

Reasons for taking a sample instead of a census include:

Leslie Bradley is an entrepreneur with a small business in Little Rock, Arkansas. Working with a local engineer/inventor, Leslie has developed a new cooking device that she thinks will revolutionize cooking. The device is a small oven that is portable and uses a gas injection system to cook meals in a fraction of the time taken in a normal oven. The new system creates a very high temperature and the gas jets are located 360 degrees around the food to be cooked, thus ensuring that the food is cooked equally on all sides. Leslie and the engineer applied for a patent and then immediately sought a relationship with a large manufacturer to produce and distribute the new oven. To her surprise, when she demonstrated it to the top three manufacturers, they all had the same reaction: "We are very interested in this new invention but we would like to see some consumer research that tells us what consumers think about the device." "Will they think the temperature is too high and represents a safety issue?" "Do they really think that a roast cooked in 6 minutes will taste the same as one roasted for 2 hours?" "How much, if any, will they be willing to pay for the added convenience of time savings?" Leslie sought the services of Weber Research, Inc. WRI was an established research firm in the city and they recommended that they use their mall facility in order to conduct some research that allowed consumers to use the device and taste the food cooked in the device. Leslie agreed but was concerned about the types of persons in the shopping mall. "They really won't represent our area since they will likely be mostly female and they will have higher incomes than the general population." WRI assured Leslie that this could be overcome by using which of the following sampling methods?

Stratified samples are most appropriate when the population is known to be "skewed."

You should obtain a listing of the population after:

Using a table of random numbers to draw a simple random sample requires that every member of the ________ must be uniquely identified (i.e., numbered).

Random online intercept sampling uses some form of random selection in order to ask visitors at Web sites to participate in surveys.

In area sampling, the two-step approach is more costly than the one-step approach because more areas and time are involved.

One of the nonprobability methods used for sampling is:

A retail store selects customers at random and gives them a card asking them to go to the store's Web site and complete a survey. This is known as invitation online sampling.

One of the differences between systematic sampling and simple random sampling is that the first one works its way through the entire population from beginning to end. The second one guarantees that the complete population will be covered, but without a systematic pattern.

In stratified sampling, the population is separated into different subgroups, and then samples are taken from all of the subgroups.