What does it mean there is no significant difference?
In principle, a statistically significant result (usually a difference) is a result that’s not attributed to chance. More technically, it means that if the Null Hypothesis is true (which means there really is no difference), there’s a low probability of getting a result that large or larger.
What is a significant difference?
A Significant Difference between two groups or two points in time means that there is a measurable difference between the groups and that, statistically, the probability of obtaining that difference by chance is very small (usually less than 5%).
What’s the difference between significant and non-significant statistics?
The Difference between Significant and Non-Significant is itself not statistically significant. The American Statistician, 60, 328-331. Rosenthal, R., & Rubin, D. B. (1979). Comparing significance levels of independent studies.
When are differences in significance aren’t significant?
There is a statistically significant difference between the groups, even though the confidence intervals overlap. [1] Unfortunately, many scientists skip hypothesis tests and simply glance at plots to see if confidence intervals overlap.
How to measure the significance of a difference?
Calculate how far each observation is from the average, square each difference, and then average the results and take the square root. This is the standard deviation, and it measures how spread out the measurements are from their mean. The standard error of some estimator. For example, perhaps the error bars are the standard error of the mean.
What happens when two results have identical statistical significance?
Two results with identical statistical significance can nonetheless contradict each other. Instead, think about statistical power. If we compare our new experimental drugs Fixitol and Solvix to a placebo but we don’t have enough test subjects to give us good statistical power, then we may fail to notice their benefits.