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SO, if you've arrived at this page, then I assume you need some help with deciphering statistical information. Bear in mind that the information below is a rough guide only, and that there are many nuances involved in Statistics which really can't be summarised in a few sentences!

What kind of Statistics should be done, and what do they mean?
    Item analysis -this is an analysis of the items, or questions in the test. This involves several steps but should tell the manufacturer which items are working hard, which items are repetitions, and whether the items relate together as predicted (e.g. all the items relating to Extraversion do in fact relate together, and crucially, do not relate to items not relating to Extraversion).

    Construct analysis - this relates to the constructs, or groups of items in the test (e.g. Extraversion is a construct). This analysis should tell you that the constructs relate together in the way predicted (e.g. that Introversion and Extraversion can be viewed as opposite ends of a continuum)

    Reliability Analysis - this analysis should be conducted using a large group of people who have taken the test, and (using a variety of techniques) their results should be compared to assess test performance

All of the above analysis involves Statistical techniques such as Principle Components Analysis (Factor Analysis) and Confirmatory Factor Analysis

Coefficient Alpha
Many text books suggest that coefficient alpha is the definitive statistic which will tell you all you need to know about the test in question. This statistic is indicative of the reliability, or internal consistency of the test, but beware! This statistic can be misleading if there is insufficient distinction between constructs (i.e. everything relates to everything else).

If you need more help than this, please contact Jane at one of the email addresses below.


If you have any questions about anything on this page, please contact Jane at jane.pollock@psy.ox.ac.uk for academic queries, or
janepollock.solutions@gmail.com for business enquiries, or janepollock.conted@gmail.com for Continuing Education students.