How does business intelligence help marketers identify changes in the purchasing patterns of customers?

 Retailers know that important life events cause customers to change what they buy and, for a short interval, to form new loyalties to new store brands. Before the advent of BI, stores would watch the local newspapers for graduation, marriage, and baby announcements and send ads in response, which is a slow, labor-intensive, and expensive process. However, by applying business intelligence techniques to their sales data, companies can identify the purchasing pattern for different products, and by observing this purchasing pattern, companies can send ads for related products to those customers.

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