Possible Duplicate:
The origin of "99 cents"
I find that there are disproportionately many price tags that say $3.95, $69.99, $198, etc. See amazon.com for example. I suppose the sellers do this because they are hoping that it will attract disproportionately more buyers than tagging it $4, $70, or $200, while actually the prices are not much different. Has there been a study that confirm this assumption?