Yamaichi Securities Co. is no longer worthy of being grouped with the Big Four securities firms, an analyst said Oct. 23, reacting to the firm's business results.Hiroshi Okumura, a professor of business management at Chuo University, was commenting on Yamaichi's 2.7 billion yen in pretax losses and 6 billion yen in net losses.Besides the payoff scandals, Okumura criticized the way the Big Four-dominated industry conducts business. Even second-tier firms followed the Big Four's lead in trying to become all-around players and encouraging a quick turnover of stock sold to individual investors, he said. "The basic structure (of domestic brokerages) has not changed," noted Okumura, who urges each brokerage to specialize in a particular field.The professor expects foreign securities firms to grow further unless domestic counterparts undergo radical structural changes. Bank-affiliated brokerages, which are vigorously underwriting corporate bonds, also will continue to gain, he said.Meanwhile, Fujiki Ito, managing director and deputy Tokyo branch manager of Smith Barney International Inc., an American brokerage, said Nomura Securities Co. did fairly well, given all the administrative penalties the firm received over the alleged payoffs to a "sokaiya" corporate extortionist. "After all, it has good corporate clients in growing industries," Ito said, thus making it easier for Nomura to collect and manage funds.The other three major brokerages, which are expected to be punished later for their alleged involvements in similar payoffs, will suffer serious setbacks in the second half of fiscal 1997, he said. Foreign brokerages, including Smith Barney, have benefited from the payoff scandals. But those firms probably will not gain any more because the stock market itself is expected to remain sluggish due to the lack of effective economic stimulus, according to Ito.