Consumer protection laws encourage sellers to be honest about the kind of product they are selling. This means that penalties must be harsh enough to deter sellers from falsely advertising a low-quality good as a high-quality good.
A seller who falsely advertised a low-quality product as high-quality was faced with the prospect of a return, in which case they would gain nothing from the transaction and would also have to pay a small fee. Here's a summary of the transactions that occurred in this variation:
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1) Was this mechanism enough to ensure that sellers didn't make false claims about their products?
A. Yes
B. No
2) If you were a buyer in this round, would you believe sellers when they advertised their products as high quality?
A. Yes
B. No
3) By the final rounds of this variation, what quality of MP3 players were being traded?
A. All high quality
B. All low quality
C. A mix of high and low quality