There are also questions about whether consumers understand privacy policies and whether they help consumers make more informed decisions. A 2002 report from the Stanford Persuasive Technology Lab contended that a website's visual designs had more influence than the website's privacy policy when consumers assessed the website's credibility. A 2007 study by Carnegie Mellon University claimed "when not presented with prominent privacy information..." consumers were "…likely to make purchases from the vendor with the lowest price, regardless of that site's privacy policies". However, the same study also showed that when information about privacy practices is clearly presented, consumers prefer retailers who better protect their privacy and some are willing to "pay a premium to purchase from more privacy protective websites". Furthermore, a 2007 study at the University of California, Berkeley found that "75% of consumers think as long as a site has a privacy policy it means it won't share data with third parties," confusing the existence of a privacy policy with extensive privacy protection.