Chi-squared (χ²) test
What Chi-squared (χ²) test means in Biology A-Level, as defined for AQA, OCR.
Definitions of Chi-squared (χ²) test
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Reference: OCR
A test that compares observed counts with expected counts to judge whether a difference is due to chance, using raw counts rather than percentages or ratios.
For categorical count data in a choice chamber, compares observed and expected frequencies.
Topics that use Chi-squared (χ²) test
- Survival and response (A-level only) (AQA A-Level)
- Patterns of inheritance (OCR A-Level)
Related terms
- Allele frequencies
- Alleles, genotypes and phenotypes
- Autosomal linkage
- Change in allele frequency over generations
- continuous variation
- Controlled variables
- critical value
- Crossing over and independent assortment
Using Chi-squared (χ²) test in the exam
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