Nina Mazar

Who they are

Biography beyond the cited work is not recorded, by rule. The publisher records list Mažar at the Joseph L. Rotman School of Management, University of Toronto, on both the 2007 paper and the 2017 one. Those are the affiliations printed at the time of publication.

The vault holds a separate note for Asaf Mazar, a different researcher, so the two should not be merged. Nina Mazar is the author of the zero-price work described here.

Key papers

Shampanier, K., Mazar, N., & Ariely, D. (2007). "Zero as a Special Price: The True Value of Free Products." Marketing Science, 26(6), 742-757. Second author.

Mazar, N., Shampanier, K., & Ariely, D. (2017). "When Retailing and Las Vegas Meet: Probabilistic Free Price Promotions." Management Science, 63(1), 250-266. First author. Abstract read.

Key ideas

On the 2007 paper, the contribution is the demonstration that zero is a special price. The authors held the price gap between two goods constant and moved both prices. With the cheaper good at a zero price, dramatically more participants chose it and dramatically fewer chose the dearer one, which standard cost-benefit reasoning does not predict. They tested social norms, mapping difficulty and affect as explanations, and the abstract names affect as the most likely.

The 2017 paper turns to a promotion that retailers use. Some offer a chance, a lottery-type promotion, of receiving the entire purchase for free. The retailers seem to share the intuition that such promotions are attractive, but it was unclear how they compare with a traditional sure promotion of the same expected monetary value. The authors compared the two across six experiments in the field and in the laboratory for planned purchases. Consumers were more likely to purchase a product promoted with the probabilistic free discount than with the sure one, and were likely to purchase more of it.

The explanation the paper favours is a diminishing sensitivity to prices. A sure discount of a given size is judged against the price in a way that makes each additional unit of saving count for less, and the chance of a free product is read differently. The authors also report that the zero price effect, transaction costs and novelty are likely not implicated. That last finding matters for readers of the 2007 paper, because it would be easy to assume that a free offer, even a probabilistic one, draws on the same pull. The authors say the data do not support that.

The 2025 study by Celia Gaertig and Joseph Simmons adds a qualification. Across five studies with 8,969 participants, they found probabilistic promotions are more effective than equivalent sure discounts only when the sure discounts are or seem trivial, and that this is inconsistent with two leading explanations, diminishing sensitivity and the overweighting of small probabilities. The 2017 and 2025 papers therefore agree on the pattern in the lottery promotions and disagree on its explanation. A reader should hold both.

For a reader of the 2007 paper, the useful point is how the same group of authors separated free as a price from free as a prize. A free product bought at a price of nothing is one thing. A one-in-ten chance of a free product is another, and the 2017 paper reports that the mechanism behind the first was likely not what drove preference for the second.

This page was written from abstracts. The papers were not read in full, so the experiments' samples and effect sizes are not reported here.

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