Pricing and product adoption · Promotion model and two field experiments
The Effects of Free Sample Promotions on Incremental Brand Sales
Bawa, K., & Shoemaker, R. (2004). Marketing Science, 23(3), 345–363.
Plain-English take
Unlike coupons, the studied free samples produced measurable long-term sales effects observable up to 12 months later. For your marketing: Separate new demand from timing shifts and substitution when evaluating free access.
How much weight to give this
3.5/5 Useful evidence with meaningful caveats
The 1–5 evidence-check score is a practical reading aid, not a formal peer review or a probability that a conclusion is true. It combines design strength (2 points), sample reporting (1), comparison/control clarity (1), and how much of the paper could be checked (1). Access affects how confidently this directory can assess a study, not the study's underlying quality. Blinding is reported separately because it is not relevant to every design.
An experiment is useful for causal evidence, but the accessible profile does not establish random assignment.
A usable sample size is not stated in the profile's accessible source.
Experimental comparison is described; randomization or control details need checking in the paper.
This profile could be checked against an abstract or metadata, not the full paper.
Double-blind? Blinding is not reported in the source reviewed; that does not establish whether blinding was or was not used.
Research question
What the authors investigated
Do free samples create incremental sales, and how much comes from purchase acceleration, cannibalization or demand expansion?
Design
The authors develop a model separating three pathways and analyze two field experiments on free-sample promotions.
Sample and setting
Two consumer packaged-goods sampling promotions; the abstract does not state sample sizes or brands.
Reported result
What the study found
Unlike coupons, the studied free samples produced measurable long-term sales effects observable up to 12 months later. Effectiveness varied substantially, even between brands in one product category; acceleration, cannibalization and expansion differed across promotions.
This is a paraphrase of the source. Check the original paper for definitions, estimates, statistical uncertainty and analysis details.
Scope and transfer
Limitations to keep in view
Consumer packaged goods, two promotions and study-specific brands; sampling economics differ from SaaS free tiers or trials. Effects varied enough that a single benchmark would be misleading.
Possible founder application
Separate new demand from timing shifts and substitution when evaluating free access. Define incremental outcomes and follow customers long enough to see whether a free experience creates durable adoption.
Evidence access
Publisher and bibliographic abstracts
INFORMS-associated bibliographic record and abstract; the two field studies and sales pathways are directly described in the abstract.
If only an abstract or metadata was available, the profile is limited to claims supported there. A paper's paywall does not change its evidentiary status, but it limits what we can substantiate from accessible text.