With a basic income, high-productivity workers increase participation while low-productivity workers reduce participation, increasing the Gini coefficient for labor earnings.

"The composition of the labor force also changes: high-productivity agents increase participation at the expense of low-productivity agents. This is reflected by the fact that although labor supply measured in hours worked drops by 7%, labor supply measured in efficiency units falls by only 2%. Consequently, the Gini coefficient for labor earnings increases from 0.55 to 0.57."