An exclusive investigation by BBC Trending looks at the YouTubers who are promoting academic cheating online. More than 250 popular YouTube channels have been paid to advertise Edubirdie, an essay-writing company. Many of the adverts, which collectively have had hundreds of millions of views, urge students to hire a “super smart nerd” to write their essays. It’s not illegal, but students caught handing in other people’s work can face serious consequences. So are the video stars misusing their power to influence and what is YouTube doing about it? The statistician Hans Rosling used data to explain how the world was changing – and often improving – more than we think and he would challenge people to examine their preconceptions. Before his death, he started working on a book about the mental biases that tend to lead us astray. Tim Harford speaks to his son Ola and daughter in law Anna who worked on the book with him. Why do people fall victim to online romance frauds? With false online profiles, doctored photographs, and convincing background stories, online fraudsters target people who are looking for love. Once they have hooked their victims, they set about stealing money from them. But what convinces people that their new relationship is so realistic that they become willing to hand over large amounts of money to someone who they may never meet. Shari Vahl reports. (Photo: Popular YouTuber Adam Saleh has advertised Edubirdie on his channel. Photo credit: Adam Saleh/YouTube)