Wikipedia:Experiment

Experiment is a stage in the development of some changes to Wikipedia policies and processes in which an idea is being tried on a temporary basis, perhaps with a limited scope of application. Many current policies, such as limiting page creation to logged-in users, began ostensibly on an experimental basis. Proposed deletion began as an experiment. Consensus had not fully formed to accept those changes, but consensus had formed to implement them on a trial basis.

Experiments can be useful for determining how an idea would work in practice. In other cases, existing knowledge may make the results of an experiment a foregone conclusion, or the risks and costs involved may outweigh the potential benefits. As Tim Vickers said in reference to restoring anonymous users' rights to create new pages, "Sticking your finger into an electric shredder is not a sensible experiment, we know exactly what the result will be and confirming the prediction will be painful."

Steps
Proposed experiments can be publicly announced at Village Pump Proposals.

As with any experiment, a hypothesis should be made and methods should be proposed for testing it. How will the results of the experiment be measured? What baseline or control group will the results be compared against? What extraneous factors need to be guarded against?

Once consensus has formed to move a proposal to an experimental stage, mark the proposed experiment with experimental. Supporters should be prepared to back up their idea with any necessary work to carry out the experiment. Once the experimental period has lapsed, the proposal should either become rejected or be accepted as a guideline or policy, based on consensus as to the merits of the proposal once the experiment is concluded. Normally, a proposal not accepted after an experiment should be marked as rejected: if even after trying the proposal in practice has not led to consensus that the proposal is a good idea, such consensus is unlikely to form.