This topic in fact fit many forums on ET. But I just let it go in the Trading and see what happens. merchants have known this for many years. They price their goods in certain numbers to improve sales. As far as I know, it seems that nine is the most popular digit in prices from something like 0.99 a burger to 99999 a luxury vehicle. So my questions is this. Does buyers and sellers in the market places have the same kind of tendency to favor some digits than the others? When you set price in your order do you prefer some digits than the others? Is there such a thing that $29 is more attractive than $31, or vice versa? Are there any technical and psychological analysis for choosing proper digits? Any scientific evidence at all?