Features and limitations

These features are currently available in version 2.5 of WEXTOR:


  • complete and incomplete experimental designs
  • experimental (between-subjects and within-subjects) factors
  • quasi-experimental (natural) factors
  • truly randomized distribution of participants to experimental conditions
  • optional distribution of participants to experimental conditions based on levels of quasi-experimental factors
  • random or fixed order of blocks
  • design is displayed visually and as ordered list

Techniques specific for Internet-based experimenting (Reips, 2002):

  • automatic avoidance of frequently made configuration errors in Web experimenting
  • non-obvious, but logical naming of files and experimental conditions
  • secure hosting
  • randomly generated continuous user IDs for enhanced multiple submission control
  • multiple site entry technique for control of sampling effects
  • implementation of the high hurdle technique for drop-out control
  • implementation of the warm-up technique that minimizes drop-out
  • automatically generated meta tags (only current content served, shield against spam entries)


  • server-side response time measurement
  • optional client-side response time measurement
  • interactive dependent measures and materials (created via content wizard)
  • visual analogue scales and radio button scales


  • no need to deal with complex HTML and Javascript code
  • works in Lab *and* Web
  • visual display of experimental design, in terms of (clickable) folders and Web pages
  • automatically generated display of experiment design and procedure, great for reports
  • automatically generated code plan (great in teaching!)
  • data available in Excel/SPSS compatible format and in log format
  • just try it ;-)