California is on the verge of making itself a guinea pig in a bold economics experiment.

By moving toward a plan to raise the statewide minimum wage to $15 an hour by 2022, the state could raise living standards for millions of workers. But it could also increase unemployment among some of the very same economically marginal workers the wage increase is intended to help.

Many economists, even some on the left, worry that a potential loss of jobs in a number of cities where wages are comparatively low could largely offset, and perhaps even more than offset, the boon of higher incomes at the bottom of the wage scale.

“Just as the benefits of this policy are likely to be greater because it covers a greater share of the work force than for past minimum wage increases, the risk of these costs is also higher,” said Ben Zipperer, an expert on the minimum wage at the liberal Washington Center for Equitable Growth. “It’s very unclear how that’s going to stack up.”

San Francisco and San Jose, both high-wage cities that have benefited from the tech boom, are likely to weather the increase without so much as a ripple. The negative consequences of the minimum wage increase in Los Angeles and San Diego — large cities where wages are lower — are likely to be more pronounced, though they could remain modest on balance.