Two variables moving together does not show that one causes the other.
Correlation coefficient r ranges from -1 to +1. Confounders and reverse causation can create spurious links. Establishing causation needs experiments or strong causal inference.
Correlation can result from chance, confounding or reverse causation. Experiments with randomisation test causation.
Common mistake: reading a high r-value as proof one variable causes the other.
Two variables moving together does not show that one causes the other.
Correlation and Causation is one of the 51 topics in Lab Methods & Biostatistics. It is rated Intermediate, so it suits learners who already know the core vocabulary. Related topics in this area include Variables, Scientific Method, Statistical Power.
Ice cream sales correlate with drownings because of summer heat.
Work through the Beginner topics in Lab Methods & Biostatistics first, such as Scientific Method, Hypothesis, Variables, then return to Correlation and Causation. Intermediate topics assume the Beginner vocabulary.
The closest topics to Correlation and Causation are Variables, Scientific Method, Statistical Power, P-Values and Multiple Testing. Comparing them side by side is a good way to see how the ideas connect.
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Correlation and Causation. To practise the whole of Lab Methods & Biostatistics, use the Lab Methods & Biostatistics quiz.
Correlation and Causation: Two variables moving together does not show that one causes the other. Variables: The independent variable is changed, the dependent variable is measured and controlled variables are kept constant. Read both side by side and note what each one explains.
Reading a high r-value as proof one variable causes the other.
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Variables and explain the difference aloud. Finally, take the Lab Methods & Biostatistics quiz and come back to this page for any question you miss.
The independent variable is changed, the dependent variable is measured and controlled variables are kept constant.
📊 Lab Methods & BiostatisticsA process of asking a question, forming a hypothesis, testing it with experiments and drawing conclusions.
📊 Lab Methods & BiostatisticsThe probability of detecting a true effect, determined by sample size, effect size and variability.
📊 Lab Methods & BiostatisticsP-values give the probability of data under the null; corrections like Bonferroni control false positives across many tests.
📊 Lab Methods & Biostatistics