I (“Wandering” Dave) moderate the Web Analytics Forum, and a few days ago, Tim M posted a question about cross-sell activities, and determining the effectiveness of some changes they recently made. In particular, he notes that, “The difficulty I’m finding is in determining the attributable growth in store sales overall to cross-sell.”
This is indeed a difficult problem that I seldom see addressed, so I wanted to note that there are a couple of ways to “buy” some measurements in situations like these. Of course, they are dependent on a few attributes of the product or service you’re selling, such as the average unit price. If you’re selling $1000 items, then you can probably afford a short 3-day coupon promotion where a web-printed coupon is brought into the store for a $25 discount. That will cost you $25 per response, but if you’re already doing something like a $20 discount promo, then it’s only an incremental $5 to collect some cross-sell data. Of course, if your average unit price is a $2.49 bottle of aspirin, you’ll need some other kind of incentive, like, “Print this coupon out and bring it in for a free buyer’s guide.”
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