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PRAs were introduced in late 2009. Nowadays, they are taking place on a number of different websites in different countries, such as for instance http://u-wantit.com/, http://1250auctions.com/ (both in English), http://ambetion.com/ (in Spanish), and https://www.youbid.nl (in Dutch). Notice that the PRA mechanism is sometimes also labelled “scratch auction”, “express auction”, or “reverse auction”. Gallice and Sorrenti (2015) document that PRAs are typically used to sell electronic products (smartphones, laptops, digital cameras) and report an average market value of the auctioned item of approximately 443€, an average fee ($c$) of 1.07€, and an average price decrese ($\mathrm{\Delta }$) of 0.53€.