Bandwagon effect

Demand for something rises when people see others choosing it.

Social influence Mainly on Category pages
Where it applies

Four of the eight page areas.

HomepageAlso applies CategoryMainly here SearchAlso applies ProductAlso applies CartNot typical CheckoutNot typical Post-purchaseNot typical

Not usually a sitewide principle. See everything at work on Category pages

How to use it

Five ways to use it, and one to avoid.

  • Add “Bestseller” and “Most popular” badges.
  • Make sort-by-popularity the default.
  • Add trending sections to the homepage.
  • Show “X% of people who viewed this bought it”.
  • Use popularity signals beyond the top sellers, as they also help specialist products.
  • Avoid: badges or popularity figures that don’t match real, current sales, as inaccurate demand information can be a banned practice under the DMCC Act 2024.
What the research found

Showing others' choices raised sales when the signal was positive.

On Amazon, showing what viewers went on to buy did no harm when the signal was negative.

Salganik and colleagues (14,341 participants) found that showing download counts made song success more unequal and less predictable. On Amazon, showing what viewers went on to buy raised sales when the signal was positive and did no harm when negative. On a wedding-vendor site, popularity information drew the most extra visits to narrow-appeal sellers.

Key research

Five sources, each checked.

Last reviewed

Salganik, Dodds & Watts (2006) Experimental Study of Inequality and Unpredictability in an Artificial Cultural Market Science Read the source Chen, Wang & Xie (2011) Online Social Interactions: A Natural Experiment on Word of Mouth versus Observational Learning J. Marketing Research Read the source Tucker & Zhang (2011) How Does Popularity Information Affect Choices? A Field Experiment Management Science Read the source Leibenstein (1950) Bandwagon, Snob, and Veblen Effects in the Theory of Consumers' Demand Quarterly J. Economics Read the source Cai, Chen & Fang (2009) Observational Learning: Evidence from a Randomized Natural Field Experiment American Economic Review Read the source
Before you use it · UK law

Badges and popularity figures must reflect real, current sales data. Giving inaccurate information about demand or availability to push a sale can be a banned practice under the DMCC Act 2024, and the CMA required Wowcher (2024) to make its popularity claims match actual sales.

This is simply a pointer to check, not legal advice. Seek legal advice before you put this principle into action.