Wansink: Purchase Quantity Decisions

Wansink et al were interested in

• How consumers decide how many units to buy?

• How frequently consumers buy certain units?

• How consumers choose certain brands?

• All of the above?

What does POP mean?

• Possibility of Purchase

• Point of Purchase

• Probability for Purchase

• Prompts for Purchases

Wansink conducted

• 1 lab study and 3 field studies

• 2 lab studies and 2 field studies

• 3 lab studies and 1 field study

• 2 field and 2 lab studies

"On sale - 6 cans for $3" would be an example of?

• Suggestive advertising

• A price reduction promotion

• A sales advertisement

• Multiple-unit pricing anchor

Study 1 was conducted.....

• In 96 stores over a two week period comparing sales of 13 products

• In 86 stores over a one month period comparing sales of 13 products

• In 86 stores over a one week period comparing sales of 13 products

• In 76 stores over a two week period comparing sales of 20 products

The products consisted of

• Soap, frozen dinners, canned soup and tuna

• Frozen pizza, bagels, loo paper, cookies

• Cookies, soap, breakfast cereal, candy

• Beans, bread, soap and frozen peas

Results were calculated

• Subtracting the average weekly sales of the products in the last 6 months from the increase in sales during the experimental week and comparing them.

• The % increase in sales between the multiple-unit anchor group and the single-unit anchor group

• Subtracting the single-unit anchor group sales from the multiple-unit anchor group sales

• All of the above

The results of Study 1 revealed that

• Multiple-unit anchors resulted in a 32% increase in sales compared to single-unit anchors and for 9 products this was statistically significant.

• Multiple-unit anchors resulted in a 45% increase in sales compared to single-unit anchors and for 12 products this was statistically significant.

• Multiple-unit anchors resulted in a 12% increase in sales compared to single-unit anchors and for 9 products this was statistically significant.

• Multiple-unit anchors resulted in a 75% increase in sales compared to single-unit anchors and for 6 products this was statistically significant.

Study 2 investigated...?

• Whether limiting the amount we can buy reduces consumer spending

• Whether sales can be increased for some products compared to others

• Whether high purchase quantity limits increase sales

• Whether reducing the amount we can buy makes consumers willing to spend more on those products.

Study 2 was...

• A lab study using a questionnaire about Campbell's soup

• A lab study where participants had to chose between buying a limited number of cans of Campbell's soup and other soups.

• An observational field study where three different promotions were rotated on 3 consecutive nights.

• A 3-week field study in 9 supermarkets across Iowa.