Mathematics A-Level
selection bias
What selection bias means in Mathematics A-Level, as defined for WJEC.
Definition of selection bias
Check what you remember
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Reference: WJEC
Systematic bias introduced by non-random methods like opportunity sampling that cannot be mitigated by merely increasing sample size.
Topics that use selection bias
- Statistical Sampling (AS Unit 2: Applied Mathematics A) (WJEC A-Level)
Related terms
- informal inference
- methodological evaluation
- Opportunity sampling
- parameter estimation
- Population
- Sample
- sample size impact
- sampling constraints
Using selection bias in the exam
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