There are many ways to look at the minimum wage increase in Los Angeles from the current $9 an hour to $15 by 2020 — some hopeful, some cautionary, all good.

For starters, uncharted territory is rapidly being charted. Los Angeles is the fourth city, and by far the largest, to enact a $15 minimum in the past year. The others are Seattle, San Francisco and Emeryville, Calif. (near San Francisco). A $15 minimum has been proposed in New York City, Washington, D.C., and Kansas City, Mo.

Opponents of higher wages — generally, business groups and their political allies — have raised the same objections in Los Angeles that have been raised since the dawn of the federal minimum wage in 1938: that higher pay will lead to layoffs and business closings or business migration. But experience and research involving actual minimum wage increases indicate otherwise: The added cost of higher wages is offset by savings from lower labor turnover and higher labor productivity.

Higher wages can also be offset by modestly higher prices, which haven’t proved measurably disruptive, in part because minimum wage increases make somewhat higher prices manageable. Wages can also be raised by paying executives and shareholders less. Whatever changes employers may have to make in Los Angeles, the long phase-in of the increase gives them time to adjust.