Stephen S.J. Hall, vice president for administration, said yesterday he will leave that post to become chief executive of Hooper-Holmes Bureau, a credit investigating firm headquartered in New Jersey.

Hall, already a director of the company, signed a three-year contract and will also serve as vice chairman of the board of directors. His office will remain in Boston.

"It's about 1 per cent as prestigious as Harvard from an ego point of view, and certainly not as prestigious as IBM or General Electric," Hall said about his new post. "But I'm a risk taker and this company allows me to take on a challenge."

Hall said Hooper-Holmes maintains a computerized file containing "the names of more than 15 million deadbeats--" people who have not paid their bills.

"We save companies a lot of grief by eliminating the bad risks." Hall said. "We are interested in people who are known bilkers."

Investigates Credit

Although Hooper-Holmes specializes in investigating consumer credit for insurance companies. Hall said he hopes to diversify the corporation's interests.

"Maybe we'll move into the energy consulting area, the market research area, or consumer information." Hall said.

The company is already engaged in some medical examination work for insurance companies.

Hooper-Holmes, established in 1898, has 130 offices with 2800 employees and $24 million in sales.

'Risk Taking'

"It's creative risk taking," Hall said, "and when you think about it that is what we've done at Harvard."

Hall originally announced that he intended to leave Harvard May 15, but said two weeks ago that he may stay until Commencement.

Although he regrets leaving his Harvard post. Hall said he told President Bok when he came to Harvard in 1971, that he would stay five years. Before coming to Harvard. Hall was director of operations support for ITT Sheraton Corporation.