HELSINKI, Finland — Universal basic income is generating considerable interest these days, from Bernie Sanders, who says he is “absolutely sympathetic” to the idea, to Mark Zuckerberg, Facebook’s chief executive, and other tech billionaires. The basic idea behind it is that handing out unconditional cash to all citizens, employed or not, would help reduce poverty and inequality, and increase individual liberty.

This discussion is still largely theoretical, though, because universal basic income hasn’t been rigorously tested. Most experiments — in the United States in the 1970s; in the Dutch city of Utrecht today — have been local and based on small sample sizes. A nonprofit organization has run a larger program in Kenya. But that effort, which is aimed at decreasing poverty in a poor country, has little bearing for advanced economies and lacks the rigor of a state-mandated nationwide program.

This is why eyes turned to Finland at the beginning of the year, when the government initiated a national test run for universal basic income. As a rich country in the European Union, with one of the highest rates of social spending in the world, Finland seemed like an ideal testing ground for a state-of-the-art social welfare experiment.

In reality, the Finnish trial was poorly designed, and is little more than a publicity stunt.

Kela, the national social-insurance institute, randomly selected 2,000 Finns between 25 and 58 years of age who were already getting some form of unemployment benefits. The subsidies were offered to people who had been unemployed for about one year or more, or who had less than six months of work experience. Participants in the trial would receive €560 (about $645) a month from January 2017 to December 2018, whether or not they came to earn any additional income.