The standard error reflects the precision of a mean and is often displayed as error bars.
SE = SD / √n. Error bars show variability or uncertainty; 95 percent confidence interval is about ±2 SE. Non-overlapping error bars suggest (not prove) a real difference.
State what error bars represent in a figure legend. Overlapping SE bars don't guarantee no difference; test statistically.
Example: 95 percent confidence intervals give a range likely to contain the true mean.
The standard error reflects the precision of a mean and is often displayed as error bars.
Standard Error and Error Bars 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 Null Hypothesis, Standard Deviation, Sampling.
A bar graph with SE bars for treatment means.
Work through the Beginner topics in Lab Methods & Biostatistics first, such as Scientific Method, Hypothesis, Variables, then return to Standard Error and Error Bars. Intermediate topics assume the Beginner vocabulary.
The closest topics to Standard Error and Error Bars are Null Hypothesis, Standard Deviation, Sampling, Statistical Power. 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 Standard Error and Error Bars. To practise the whole of Lab Methods & Biostatistics, use the Lab Methods & Biostatistics quiz.
Standard Error and Error Bars: The standard error reflects the precision of a mean and is often displayed as error bars. Null Hypothesis: The default assumption of no effect or difference, which data may lead us to reject. Read both side by side and note what each one explains.
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 Null Hypothesis and explain the difference aloud. Finally, take the Lab Methods & Biostatistics quiz and come back to this page for any question you miss.
The default assumption of no effect or difference, which data may lead us to reject.
📊 Lab Methods & BiostatisticsA measure of spread showing how far values typically lie from the mean.
📊 Lab Methods & BiostatisticsSelecting a representative subset of a population to study using methods such as random quadrats.
📊 Lab Methods & BiostatisticsThe probability of detecting a true effect, determined by sample size, effect size and variability.
📊 Lab Methods & Biostatistics