Qudian, a mainland Chinese online loan provider, has seen its New York shares tumble sharply since listing in October, prompting an apology from CEO and founder Luo Min during the weekend, who says he regrets not doing a better job of communicating with the media to counter criticism levelled at the company. In a WeChat posting the 34-year-old Luo conceded it was "wrong" to turn away media interviews during a sensitive period when critics lashed out at the firm and other lenders,...