degrees of freedom
What degrees of freedom means in Psychology A-Level, as defined for AQA, OCR.
Definitions of degrees of freedom
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Reference: OCR
A value calculated for a Chi-square test, found using df = (r - 1) × (c - 1) for a test of association or df = k - 1 for a goodness-of-fit test.
A figure the table may ask for instead of the number of participants or of pairs, worked out where the test needs it.
The number of rows minus one, multiplied by the number of columns minus one, written as (rows - 1)(columns - 1).
Topics that use degrees of freedom
- Algebra (AQA A-Level)
- Handling data (AQA A-Level)
- D.2 – algebra (OCR A-Level)
Related terms
- levels of significance
- type 1 and type 2 errors
- bar chart
- calculating the Sign test
- causation and third variables
- central tendency
- Chi-square test
- choosing a statistical test
Using degrees of freedom in the exam
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