The correct answer would be extensive definitions of a large number of words since this type of dictionary doesn't limit the amount of words that are in definitions.
Answer:
Difficult part is to determine which variable is affecting the other and up to what extent.
Explanation:
The most difficult part to calculate while determining correlation is to access which variable is impacting the other variable/variables.
Thus, a Factor analysis is carried out to determine the relation of each variable with the other variables.
I need a more detailed explanation to help you.
