VANCOUVER - Canada has for a second year denied visas to numerous researchers hoping to attend a major artificial intelligence conference, but has reversed some of those denials after coming under pressure to review them.

Katherine Heller, an AI researcher and co-chair of diversity and inclusion at the NeurIPS conference, says that the government initially denied 30 researchers, mostly from African countries, but that it has since approved 15 on further review.

The numbers come from Black in AI, a group hosting a workshop in conjunction with the conference, which saw about a third of its attendees denied visas for last year's conference in Montreal and started to raise concerns after seeing a similar levels of denials for this year's event in Vancouver.

Victor Silva, one of the workshop chairs at Black in AI, said it was very frustrating that the group has had to work so hard to bring a diversity of views to what is the world's largest AI conference.

Silva, a researcher at the University of Alberta, said artificial intelligence learns from data and that without those diverse views development of the technology can lead to biased learnings and skewed outcomes.

A spokesperson from Immigration, Refugees and Citizenship Canada says the government understands the disappointment of those whose visa applications were refused, but that all applications from around the world are assessed equally against the same criteria.

This report by The Canadian Press was first published Nov. 15, 2019.