What does the word Significance mean in null hypothesis test in statistics?
In statistics, a result is called ‘statistically significant’ if it is unlikely to have occurred by chance. “A statistically significant difference” simply means there is statistical evidence that there is a difference; it does not mean the difference is necessarily large, important or significant in the common meaning of the word. The significance level of a test is a traditional frequentist statistical hypothesis testing concept. In simple cases, it is defined as the probability of making a decision to reject the null hypothesis when the null hypothesis is actually true (a decision known as a Type I error, or “false positive determination”). The decision is often made using the p-value: if the p-value is less than the significance level, then the null hypothesis is rejected. The smaller the p-value, the more significant the result is said to be.
