15.3 Statistical test using the binomial distribution

AQA Edexcel OCR A OCR B (MEI)
You can use the binomial distribution to perform a hypothesis test if the conditions for a binomially distributed event are met:

- there is a fixed number of trials (\(n\)),
- there are only two possible outcomes (success and failure),
- there is a fixed probability of success (\(p\)), and
- the trials are independent of each other.

To perform the test:

- Define the test statistic
- Determine whether a one-tailed or two-tailed test is needed
- Identify the null and alternate hypotheses accordingly
- Calculate the probability of the test statistic taking the observed value or higher/lower, assuming the null hypothesis to be true
- Compare this to the significance level, and either reject or cannot reject the null hypothesis
- Conclude with a statement in context of the question
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