Personally, I think using big data is quite an effective way of marketing. Many times I have found useful products that matched my needs through the advertisements on social media. Though I do think companies should be more transparent on what kind of data or algorithms they use to achieve such accurate advertisements. There should also be an opt-out option for anyone who does not want their data to be used by any means. I believe it's okay to use data for marketing and advertisement since it poses no harm to the consumers. However, it's never okay to use data for other purposes like political campaigns or selling it for benefits...
