Question

Choose the best method for choosing a sample and the best method to collect data. Remember to think about the definitions and the pros and cons of each before choosing your answers.

a) A new restaurant has been open for three months and wants feedback from its customers. They plan to give a survey to every 5th customer.
Census or sampling method:
Collection method:
b) A dog food claims to make dogs' coats shinier and healthier looking. A researcher wants to test the claims. They plan to randomly select pet store shoppers to participate and assign them to two groups.
Census or sampling method:
Collection method:
c) The Department of Homeland Security wants to test a computer virus that it has developed to combat hackers. They plan to test run the virus on randomly selected computers with pre-set "hacker" programs.
Census or sampling method:
Collection method:

Answer 1

The appropriate sampling methods for the different scenarios are systematic sampling for the restaurant surveys, a randomized controlled trial for testing dog food, and simple random sampling for the DHS computer virus test. Collection methods include questionnaires, direct observation, surveys, and automated tracking systems.

Step-by-step explanation:

In case a), a new restaurant is seeking feedback from its customers using a systematic sampling method by giving a survey to every 5th customer. This systematic approach ensures that there is a regular interval in selecting members from the population, which can help reduce bias compared to convenience sampling. The best collection method in this scenario could be a questionnaire handed out to customers which would likely provide timely and relevant feedback.

In case b), the researcher is using a randomized controlled trial, which falls under the sampling method. They are randomly choosing pet store shoppers and then assigning them to two groups, likely one with the dog food in question and the other with different food. This method can effectively test the claim because it compares results between the controlled group and the group exposed to the variable being tested. The collection method here would involve direct observation and possibly surveys or interviews with the pet owners about their observations.