A new release of Zocalo (2011.2) is now posted on Sourceforge. The only change in this release is a fix to a bug in the RPC Server, which is only likely to be used in lab experiments based on the DB version. The feature is normally left turned off, since it has a dire impact on security. I only posted the tar.gz (linux, etc.) version. If you need Windows, let me know.
A new release of Zocalo (2011.1) is now posted on Sourceforge. The only change in this release is a fix to a bug noticed by people working on both Experiment and PredictionMarket platforms. If you downloaded the November release, you should upgrade to this version soon.
There's a bug-fix release (2009.3a) available now that fixes a problem in display of numbers for Experiments.
I've just uploaded a new release that replaces virtually all arithmetic with numbers using Java's BigDecimal. This fixes a source of bugs that has bitten us numerous times. The doubles that we used to rely on don't exactly represent the decimal numbers that users type in, so it always looked like trades were done for amounts slightly different than users requested.
This requires a major change to the database representation, so existing prediction markets will have to be restarted. If anyone has existing databases that they'd like to preserve, please contact me. If there's demand for this, I will investigate the possibility of converting old databases. In the past We always managed to provide a clean upgrade path; we'll endeavor to ensure that this kind of change isn't necessary again.... read more
I've just uploaded a new release that supports two new kinds of experiments (Mark-to-Market with lending, and an Insider Manipulation experiment with short selling), and the Prediction Markets have responsive UIs based on AJAX, so the prices and charts update automatically when other users trade.
You can read the Release Notes and download the files at https://sourceforge.net/projects/zocalo/files.