Elaine Bergan is president of a bank with several branches E

Elaine Bergan is president of a bank with several branches. Elaine has been exploring the impact of service satisfaction with bank performance and is convinced that she can improve the bank’s financial performance if she can improve customer satisfaction. She has been contemplating a proposal from the marketing research firm, Business Insights, to start a program of improving customer satisfaction. Business Insights has recommended a survey of bank customers to establish gaps in service as perceived by the customers. Elaine knows that the bank has a list of all the customers and that this information is on an electronic database complete with mailing addresses and, for those having Internet service, email addresses. At the next meeting, Elaine expresses concern that sending a questionnaire to all bank customers is an inconvenience to the customers and she does not want to create more hassles for them. The researchers from Business Insights assure Elaine that they can get the needed information for as few as a couple of hundred customers and that the results will be representative of all bank customers. Which sample method should Business Insights use for this project?

the class is a business class and statistics class alll in one. please help me with this question.

Solution

It seems that there are two different groups of customers.

First group : With mailing addresses , dont have internet service

Second group: With email adresses, have internet sevice.

So Buisness insights should divide the population in two groups and then select the some cutomers (as required) randomly from each group.

In term of sampling, groups are known as strata and sampling method as stratified sampling.