BRAINCAKEHypothesis Testing
Ecological data vary naturally, so a difference or trend in results could be due to chance. Statistical tests tell us how likely it is that a result occurred by chance.
1. State a null hypothesis (H0): there is no significant difference between the samples, or no significant correlation between the variables. For example: there is no significant difference in the mean shell height of limpets on exposed and sheltered shores.
2. State the alternative hypothesis (H1): there is a significant difference or correlation.
3. Choose the correct test:
- correlation between two variables: Spearman's rank
- difference between two means of normally distributed data: Student's t-test
Sign in free to see the rest of this lesson, the R.E.C.I.P.E. recall steps and the quiz
BrainCake is free. Make an account in seconds and pick up where this page stops.
Key terms in this lesson
- degrees of freedom
- The number of categories in a statistical test minus one.
More in The Nature of Ecosystems
- Quadrats
- ACFOR Scale
- Point Quadrats
- Permanent Quadrats
- Transects
- More Ecological Techniques
- Spearman's Rank Correlation Coefficient
- Student's t-Test
All 39 lessons in The Nature of Ecosystems · All Edexcel A-level Biology topics