(Corrects to Tuesday from Wednesday in second paragraph) Dec 16 (Reuters) - Shares of Upstart Holdings Inc jumped 30% in market debut on Wednesday, giving the cloud-based artificial intelligence (AI) lending platform a market capitalization of $1.88 billion. Upstart’s shares opened at $26 on the Nasdaq, above their initial public offering (IPO) price of $20 apiece. The firm raised $240.4 million in its IPO on Tuesday.