Disclaimer: The Psychometrics page of the methodologyshop is still under construction. Especially for questions on CTT and IRT reach out to us via methodologyshop@utwente.nl.
Factor analysis
With Factor Analysis you can analyze how many different factors (think of concepts or constructs) are measured by your scale. Watch the mini lectures to get started:
In case you have questions regarding confirmatory factor analysis please reach out to us via methodologyshop@utwente.nl.
You can find information on how to run a factor analysis in R the R-Manual.
Classical Test Theory (CTT)
You can find information on how to perform CTT analyses in R the R-Manual.
Item response theory (IRT)
You can find information on how to perform IRT analyses in R the R-Manual.