WebExp2 Experimenter's Manual - School of Informatics - University ...

3.1.4 Server commands
The server accepts commands while running in the console, allowing the display of summary statistics. Available
commands are listed in table 2 To invoke a server command, type a letter at the console followed by return.
Try h first to see the available commands.
Figure 2: Server runtime commands. These are initiated by typing the letter followed by return.
q (Q)uit hard quit — close the server, terminating connections
w (W)ait quit the server, after waiting for connections to close
d (D)ump dump current state records to file (also done automatically before quitting)
i (I)nfo print summary server state information
c (C)onnections show current connection details
e (E)xperiments show all experiments
a (A)ctive show active experiments (those available to clients)
r (R)unning print details of running experiments (those with connections)
h (H)elp print command list
This feature was added primarily to allow a clean shut down of the server while it is administering experiments.
The quit and wait commands save current records before stopping the server, which is essential for maintaining
experiment completion records, and these commands should be used in preference to ctrl-c for stopping the
server.
The wait command additionally attempts to wait for running experiments to complete before stopping the
server, though this is not yet implemented.
You can also use ctrl-c to perform an unconditional quit. This stops Java instantly and is useful if you have
a problem. However it does not save records.
3.2 Storage of results and logs
As clients connect to your server and administer the experiments, information is returned each time a subject
completes an experiment. You should get incrementally numbered files created on your system.
Relative to the release directory, you will have a data directory data/experimenter/experiment for your
experiment, and the following directories will be created within this for storing results: results, subjects and
logs. Each will contain numbered files in the format experiment+number.xml.
Each time someone participates in an experiment, a unique ID is generated to identify that instance of the
experiment. The IDs are saved to the uidmappings file in the data directory, along with information identifying
the experiment and the number used to save the results files. Results files are saved in XML format and are
easily processed to extract the information you want.
3.2.1 Results
The results file records all response information for each ‘question’ in the experiment. This ranges from a simple
button press to textual input and timing information. Identifying properties are also output so you know where
each response came from, even with a randomised experiment.
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