The Rhode Island pension system has fired a hedge fund whose investments lost $15 million over the past two years.The state invested $50 million with Luxor Capital Partners in March, 2014, and by the end of February the value of those assets had declined to $35 million, according to figures from the State Investment Commission.After showing concern about Luxor's performance in January, the State Investment Commission Wednesday voted unanimously to pull the plug on the hedge [...]