Consumers who are not regular yogurt eaters are polled and asked to rate on a 1 to 9 scale the likelihood that they would buy a certain yogurt product at least once a month; 1 means very unlikely, 9 means very likely. The product is hypothetical and described by three factors: cost ("C"-low, medium, and high), sensory quality ("S"-low, medium, and high), and nutritional value ("N"-low and high). The plan was to poll three consumers for each product type, but it became clear early in the experiment that people were unlikely to buy a high-cost, low-nutrition, low-quality product, so only one consumer was polled for that combination. Each consumer received one of the eighteen product descriptions chosen at random. The data follow:
Analyze these data for the effects of cost, quality, and nutrition on likelihood of purchase.