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psychlotron.org.uk
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Name of resource: assessing reliability & validity
Author(s): Aidan Sammons
Specification: AQA-B
Details: Materials for a lesson on assessing reliability & validity of psychological measures.  Contains:

1: stress questionnaire - prepare the ground for this lesson by administering it earlier in the course.  I use
it for a prior lesson oin self-report measures.  You need to do this so you can get data for test-retest.
2: hassles questionnaire - use this to assess concurrent validity.  NB: NEITHER OF THESE QUESTIONNAIRES ARE
VALIDATED.  USE THEM ONLY FOR DEMONSTRATION PURPOSES.
3: a spreadsheet for calculating correlations between sets of test scores.  I know you should use Cronbach's
Alpha for this sort of thing but I don't want to scare my students.  The sheet is set up to calulate (using Excel's
CORREL function) the correlation coefficients (a) between students' current and earlier scores of the stress questionnaire;
(b) between the separate scores they calculate for the odd and even items on the questionnaire; and (c) between
their scores on the stress questionnaire and on the hassles scale.  You may need to adjust the formulae depending on
the size of your classes.
4: slides showing how the concepts of reliability and validity break down and briefly outlining some different
types of reliability and validity.