Suppose you want to determine if there are differences in the average prices among items at three local supermarket chains.If a block design were used,what would be an appropriate blocking variable for this study?
A)A supermarket
B)A type of item (e.g. ,beverages,medications,condiments,etc. )
C)None of the above

Question

Quizplus · Accepted Answer

Blocking variables are used to account for variability that might affect the response variable but is not the primary focus of the experiment. In this case, using a type of item as a blocking variable would help control for differences in item categories, ensuring that the comparison among supermarket chains focuses on price differences rather than differences in the types of items sold.

Suppose You Want to Determine If There Are Differences in the Average