A PubMatic study asked about 500 Internet users how they feel about advertisers tracking their online activities. MediaPost reports the study found that the anonymity of the data and how the data is used matters to respondents. Once respondents understood that only anonymous data was used for ad targeting, 40 percent changed their response from disapproving of the practice to approving of it. PubMatic's vice president of marketing said, "Everyone knows the user's privacy is paramount and that we provide a service to them. Understanding the 'how' and the 'why' changes everything."