International A Level Biology / Ecology

Null hypotheses and choosing a statistical test revision notes

Edexcel International A Level Biology (YBI11), chapter 15: Ecology, specification point A.1.9, U6.1. Part of the full course.

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A null hypothesis predicts no significant difference or correlation, with any pattern in the data due to chance. Choosing the right statistical test and comparing its calculated value with a critical value lets you decide whether the result is significant.

More lessons in Ecology

• Population, community, habitat and ecosystem
• Succession: from colonisation to climax
• Abiotic factors and population size
• Biotic factors: predation, competition and disease
• How the niche explains distribution and abundance
• Core practical 11: random sampling with quadrats
• Core practical 11: transects and abiotic measurements
• Spearman's rank correlation coefficient
• Student's t-test
• The chi-squared test