Experiments can now test many different treatments at once, more accurately

Researchers have found a new way to design experiments that test many different things at the same time. This means studies can now get clearer results, even when testing complex ideas like different types of cash transfers or marketplace incentives.

For decades, experiments mostly tested one thing at a time, or a few simple variations. This new method lets researchers explore a much wider range of options in a single study, like how different combinations of support affect people. It means we can learn more efficiently about what actually works in complex situations, rather than just comparing a few simple choices.