Question

A national coat retailer remodeled their stores in February. After the remodel, their average sales dropped by 5%. Upon looking at the sales figures, the CEO deemed this remodel a failure and fired the floor plan executive.

What is wrong statistically?

• This is a voluntary response sample. Due to the sampling, the results of the sample will not likely represent the views of the population.
• The source of the study is questionable, since they have an interest in the poll.
• There is missing information that would be critical to understanding the results of the poll.
• There is a possibility of a history effect. The time of year has a direct impact on the results of the poll.
• Just because two variables are correlated does not necessarily mean that one causes the other.

Answer 1

The answer is:

There is missing information that would be critical to understanding the results of the poll.

We do not have sufficient information about why the model failed. We would need more data from the remodel and the sales figures in order to make any inferences. There could have been a seasonal effect but without actual monthly data or more information we cannot be sure.

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