Week 1 Assignment: Comparing Sampling Methods Q and A

A television station plans to send a crew to a polling center on an election day. Because they do not have time to interview each individual voter, they decide to count voters leaving the polling location and ask every 20th voter for an interview. What type of sampling is this? Select the correct answer below: Simple random sampling Cluster sampling Stratified Sampling Systematic sampling Convenience sampling 2. In order to study the shoe sizes of people in his town, Billy samples the population by dividing the residents by age and randomly selecting a proportionate number of residents from each age group. Which type of sampling is used? Select the correct answer below: Systematic sampling Stratified sampling Convenience sampling Cluster sampling 3. The management of a large airline wants to estimate the average time after takeoff taken before the crew begins serving snacks and beverages on their flights. Assuming that management has easy access to all of the information that would be required to select flights by each proposed method, which of the following would be reasonable methods of stratified sampling? Select all that apply. For each day of the week, randomly select 5% of all flights that depart on that day of the week. This study source was downloaded by from CourseH on :26:04 GMT -06:00 Divide all flights into the following 4 groups on the basis of scheduled departure ime: before 9:00 am, 9:00 am to 1:00 pm, 1:00 pm to 5:00 pm, and after 5:00 pm. Randomly select 5% of the flights in each group. For each crew member the airline employs, randomly select 5 flights that the crew member works. Divide the airports from which the airline's flights depart into 4 regions: Northeast, Northwest, Southwest, and Southeast. Randomly select 5% of all flights departing from airports in each region. 4. To study the mean respiratory rate of all people in his state, Frank samples the population by dividing the residents by towns and randomly selecting 12 of the towns. He then collects data from all the residents in the selected towns. Which type of sampling is used? Select the correct answer below: Convenience sampling Systematic sampling Stratified sampling Cluster sampling 5. When is stratified sampling appropriate? Select the correct answer below: Stratified sampling is a good choice when the population has multiple distinct groups that are each likely to be representative of the population as a whole. Stratified sampling is a good choice when the population has multiple distinct groups that are internally homogenous but not representative of the population as a whole. Stratified sampling is a useful method if the population is not well understood or there are no groups within the population that need to be analyzed individually. Stratified sampling is a useful method when the individuals in the population are generated in a continuous stream, like on an assembly line.