In order to configure an experiment using the OSA software, you will first need to create a configuration and an experiment group (or as many distinct ones as you may need). Add a configuration to the configuration group you have created, choosing OSA out of the available experiment types, and click "Add". Once it has been added, click the "Edit" icon.

At the Edit screen, click "Configure parameterization". This parameter set, which will contain all the information required to run an experiment, can then be used for different experiments, as many times as required, since it is independent of the experiments that are run.

A new browser window will be opened for the experiment setup. The first step in the parametrization of the experiment is to enter the maximum number of bidders in the auction, and the minimum required to start the experiment. The default value of each is 2, but the specific needs of your experiment will determine the values you choose.

Screen Capture: Main Configuration Screen

The conversion factor is simply the rate at which experimental currency will be converted to real-world currency. The default value is 1, but the rate you choose will depend on your budget.

If you want the subjects to know how many rounds of different auction regimes will be run, check 'Yes' for 'Show number of auctions?'

For institution-specific instructions to be displayed to subjects whenever the auction institution changes, check 'Yes' for 'Show Instructions.' If you would like to provide your own URLs for subject instructions, click the 'Sources' button and enter them, otherwise defaults have been provided. The default time provided for subjects to read the instructions is 1 minute 30 seconds.

To play the experiment over multiple periods, click 'Add Regime', and select the desired institution from the list. Click the button under 'Min/Max Values' for that regime to enter the lowest and highest values for bidders.

Screen Capture: Bidder Values

Once you click 'Randomize', the values will be randomly assigned to bidders using a uniform distribution between the minimum and maximum values entered.

Next: Configuring institution-specific parameters