Bias in machine learning may be problematic even for tech giants like Amazon who are at the forefront of this emerging field. A new report from Reuters shows the technology giant had to get rid of an internal project used to vet job applications after the recruiting tool displayed an inherent bias against women. The team responsible for this tool had been working on computer projects since 2014 to analyze job applicants' resumes. Amazon's hiring tool used artificial intelligence to give candidates scores from one to five, similar to how online shoppers rate products on the site. "Everyone wanted this holy grail," one individual familiar with the project told Reuters.