As long as you understand and practice a data-to-decisions framework like BADIR, you can use simple techniques to optimize your day to day decisions.
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All of these kinds of questions would be better answered when the marketing manager knows how to leverage the customer data BADIR - 5 steps Analytics Process they have.
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And yes, analytics when done right, is a structured process ( BADIR is one such approach), is learnable by most business professionals and the analysis part is doable in MS Excel.
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