Glossary of statistical terms
Validity characterises the extent to which a measurement procedure is capable of measuring what it is supposed to measure. Normally, the term "validity" is used in situations where measurement is indirect, imprecise and cannot be precise in principle, e.g. in psychological IQ tests purporting to measure intellect. (In direct measurements of physical quantities - e.g. length, duration, weight - the concept of "accuracy" is normally used rather than "validity".)
To establish validity, various statistical techniques and concepts are used: Pearson correlation coefficient (to quantify correspondence between measurements and and an accepted "true" value - e.g. correlation between SAT scores and subsequent college grades); factor analysis (to establish latent interrelation between variables), regression .
For different categories of validity in psychometrics see face validity , content validity , concurrent validity , predictive validity , construct validity , convergent validity , divergent validity .
Want to learn more about this topic?
Statistics.com offers over 100 courses in statistics from introductory to advanced level. Most are 4 weeks long and take place online in series of weekly lessons and assignments, requiring about 15 hours/week. Participate at your convenience; there are no set times when you must to be online. Ask questions and exchange comments with the instructor and other students on a private discussion board throughout the course.
This course covers the issues you need to address in designing studies to produce statistically valid conclusions. Topics covered in the course include: overview of validity and bias, selection bias, information bias, and confounding bias.
The course describes the various methods used for modeling and evaluating survival data, or time-to event data.