International Personality Item Pool is a public domain personality testing system. The Myers-Briggs Type Indicator test and other major personality testing systems are closed, proprietary systems – the scoring systems are opaque. They can’t be experimented with and modified or, most importantly, tested by those outside of the organizations who own them.
International Personality Item Pool is an open system for behavioral scientists, created by the Oregon Research Institute.
This IPIP Website is intended to provide rapid access to measures of individual differences, all in the public domain, to be developed conjointly among scientists worldwide. Later, the site may include raw data available for reanalysis; in addition, it should serve as a forum for the dissemination of psychometric ideas and research findings.
International Personality Item Pool web site.
The IPIP-NEO an online test from a doctor Portland State University .