New York--Shares of Yahoo! Inc. rose on Dec. 28 after a Merrill Lynch analyst raised estimates for the online media company's fourth-quarter results, citing improvements in the online advertising market and Yahoo!âs takeover of Hotjobs.com Inc. Yahoo!'s stock climbed 96 cents to $18.73 in late-morning trading. Earlier in the day, Merrill Lynch analyst Henry Blodget raised his fourth-quarter revenue estimate for Yahoo to $175 million from $168 million.